0001048268-20-000033 | 10-K | XBRL Viewer

DEI Document - USD ($) $ in Thousands	12 Months Ended
DEI Document - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 02, 2020
Entity Information [Line Items]
Entity Registrant Name	IES Holdings, Inc.
Document Type	10-K
Document Period End Date	Sep. 30, 2020
Entity File Number	001-13783
Entity Incorporation, State or Country Code	DE
Document Annual Report	true
Document Transition Report	false
Amendment Flag	false
Entity Central Index Key	0001048268
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--09-30
Entity Tax Identification Number	76-0542208
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Address, Address Line One	5433 Westheimer Road
Entity Address, Address Line Two	Suite 500
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77056
City Area Code	713
Local Phone Number	860-1500
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		20,745,974
Documents Incorporated by Reference	Certain information contained in the Proxy Statement for the 2021 Annual Meeting of Stockholders of the Registrant to be held on February 25, 2021, is incorporated by reference into Part III of this Annual Report on Form 10-K.
Entity Public Float	$ 148,100
Common Stock [Member]
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	IESC
Security Exchange Name	NASDAQ
Preferred Stock [Member]
Entity Information [Line Items]
Title of 12(b) Security	Rights to Purchase Preferred Stock
Trading Symbol	IESC
Security Exchange Name	NASDAQ

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Statement of Financial Position [Abstract]
Cash and cash equivalents	$ 53,577	$ 18,934
Accounts receivable	213,016	186,279
Retainage	40,878	29,214
Inventories	24,889	21,543
Costs and estimated earnings in excess of billings	29,937	29,860
Prepaid expenses and other current assets	9,153	10,625
Total current assets	371,450	296,455
Property and equipment, net	24,589	25,746
Goodwill	53,763	50,622
Intangible assets, net	39,357	26,623
Deferred tax assets	33,803	40,874
Operating right of use assets	31,786	0
Other non-current assets	5,780	4,938
Total assets	560,528	445,258
Accounts payable and accrued expenses	186,710	152,909
Billings in excess of costs and estimated earnings	55,739	40,563
Total current liabilities	242,449	193,472
Long-term debt	217	299
Operating long-term lease liabilities	20,530	0
Other non-current liabilities	12,215	1,945
Total liabilities	275,411	195,716
Noncontrolling interest	$ 1,804	$ 3,294
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Preferred stock, value	$ 0	$ 0
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	100,000,000	100,000,000
Common Stock, Shares, Issued	22,049,529	22,049,529
Common Stock, Shares, Outstanding	20,762,395	21,165,011
Common stock, value	$ 220	$ 220
Treasury Stock, Shares	1,287,134	884,518
Treasury stock, value	$ (24,499)	$ (12,483)
Additional paid-in capital	200,587	192,911
Retained earnings	107,005	65,600
Total stockholders' equity	283,313	246,248
Total liabilities and stockholders' equity	$ 560,528	$ 445,258
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Revenues	$ 1,190,856	$ 1,076,996	$ 876,828
Cost of services	962,897	894,893	726,866
Gross profit	227,959	182,103	149,962
Selling, general and administrative expenses	170,911	140,575	123,920
Goodwill impairment expense	6,976	0	0
Contingent consideration	11	374	103
Loss (gain) on sale of assets	0	52	(15)
Operating income	50,083	41,850	25,954
Interest expense	777	1,857	1,946
Other (income) expense, net	12	(148)	(340)
Income from operations before income taxes	49,294	40,141	24,348
Provision for income taxes	8,740	6,663	38,151
Net income (loss)	40,554	33,478	(13,803)
Net (income) loss attributable to noncontrolling interest	1,045	(272)	(354)
Comprehensive income (loss) attributable to IES Holdings, Inc.	$ 41,599	$ 33,206	$ (14,157)
Earnings (loss) per share, basic	$ 1.96	$ 1.56	$ (0.67)
Earnings (loss) per share, diluted	$ 1.94	$ 1.55	$ (0.67)
Weighted Average Number of Shares Outstanding, Basic	20,795,892	21,082,012	21,196,388
Weighted Average Number of Shares Outstanding, Diluted	21,092,410	21,315,245	21,196,388

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]
Stockholders' Equity Attributable to Parent, Beginning Balance at Sep. 30, 2017	$ 236,704	$ 220	$ 6,898	$ 196,955	$ 46,427
Shares, Issued, Beginning Balance at Sep. 30, 2017		22,049,529	712,554
Issuances under compensation plans	0		$ 5	(5)
Issuances under compensation plans, shares			520
Acquisition of treasury stock	(2,059)		$ (2,059)
Acquisition of treasury stock, shares			(133,459)
Options exercised	$ 11		$ 15	(4)
Options exercised, shares	1,500		1,500
Non-cash compensation	$ (136)			(136)
Decrease (increase) in noncontrolling interest	44				44
Net income (loss) attributable to IES Holdings, Inc.	(14,157)				(14,157)
Stockholders' Equity Attributable to Parent, Ending Balance at Sep. 30, 2018	220,407	$ 220	$ 8,937	196,810	32,314
Shares, Issued, Ending Balance at Sep. 30, 2018		22,049,529	843,993
Issuances under compensation plans	0		$ 5,942	(5,942)
Issuances under compensation plans, shares			501,797
Acquisition of treasury stock	$ (9,802)		$ (9,802)
Acquisition of treasury stock, shares	(467,819)		(564,822)
Options exercised	$ 0		$ 314	(314)
Options exercised, shares	22,500		22,500
Non-cash compensation	$ 2,357			2,357
Cumulative Effect of New Accounting Principle	80				80
Net income (loss) attributable to IES Holdings, Inc.	33,206				33,206
Stockholders' Equity Attributable to Parent, Ending Balance at Sep. 30, 2019	$ 246,248	$ 220	$ 12,483	192,911	65,600
Shares, Issued, Ending Balance at Sep. 30, 2019	22,500	22,049,529	884,518
Issuances under compensation plans	$ 0		$ 1,708	(1,708)
Issuances under compensation plans, shares			120,197
Acquisition of treasury stock	$ (7,697)		$ (13,808)	6,111
Acquisition of treasury stock, shares	(263,160)		(528,563)
Options exercised	$ 34		$ 84	(50)
Options exercised, shares	5,750		5,750
Non-cash compensation	$ 3,323			3,323
Decrease (increase) in noncontrolling interest	(194)				(194)
Net income (loss) attributable to IES Holdings, Inc.	41,599				41,599
Stockholders' Equity Attributable to Parent, Ending Balance at Sep. 30, 2020	$ 283,313	$ 220	$ 24,499	$ 200,587	$ 107,005
Shares, Issued, Ending Balance at Sep. 30, 2020	5,750	22,049,529	1,287,134

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Statement of Cash Flows [Abstract]
Net income (loss)	$ 40,554	$ 33,478	$ (13,803)
Bad debt expense	1,864	552	421
Deferred financing cost amortization	152	318	288
Depreciation and amortization	12,508	9,557	8,860
Loss (gain) on sale of assets	0	(52)	15
Non-cash compensation	3,323	2,357	(136)
Goodwill impairment expense	6,976	0	0
Deferred income taxes	5,122	5,681	38,151
Accounts receivable	(25,389)	(35,254)	(7,574)
Inventories	(2,822)	(684)	(3,970)
Costs and estimated earnings in excess of billings	435	1,586	(17,840)
Prepaid expenses and other current assets	(9,355)	(7,171)	(2,250)
Other non-current assets	510	(444)	274
Accounts payable and accrued expenses	20,122	22,472	6,584
Billings in excess of costs and estimated earnings	13,967	6,683	3,570
Other non-current liabilities	8,774	(459)	(336)
Net cash provided by operating activities	76,741	38,724	12,224
Purchases of property and equipment	4,745	6,300	4,563
Proceeds from sale of assets	104	502	108
Cash received (paid) in conjunction with business combinations	(28,952)	50	(7,406)
Net cash used in investing activities	(33,593)	(5,748)	(11,861)
Borrowings of debt	592,768	89,261	168
Repayments of debt	(592,756)	(119,508)	(177)
Finance lease payment	(215)	0	0
Distribution to noncontrolling interests	(639)	(240)	(349)
Purchase of treasury stock	(7,697)	(9,802)	(2,059)
Issuance of shares	34	0	11
Net cash used in financing activities	(8,505)	(40,289)	(2,406)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	34,643	(7,313)	(2,043)
CASH, CASH EQUIVALENTS and RESTRiCTED CASH, beginning of period	18,934	26,247	28,290
CASH, CASH EQUIVALENTS and RESTRICTED CASH, end of period	53,577	18,934	26,247
Cash paid for interest	782	1,743	1,684
Cash paid for income taxes (net)	$ 323	$ 1,370	$ 2,839

Business	12 Months Ended
Business	Sep. 30, 2020
Accounting Policies [Abstract]
Business Description and Basis of Presentation [Text Block]	1. BUSINESS Description of the Business IES Holdings, Inc. is a holding company that owns and manages operating subsidiaries that design and install integrated electrical and technology systems and provide infrastructure products and services across a variety of end-markets, including data centers, residential housing and commercial and industrial facilities. Our operations are currently organized into four principal business segments, based upon the nature of our current services: •Communications – Nationwide provider of technology infrastructure services, including the design, build, and maintenance of the communications infrastructure within data centers for co-location and managed hosting customers for both large corporations and independent businesses. •Residential – Regional provider of electrical installation services for single-family housing and multi-family apartment complexes. •Infrastructure Solutions – Provider of electro-mechanical solutions for industrial operations, including apparatus repair and custom-engineered products such as generator enclosures to be used in data centers and other industrial applications. •Commercial & Industrial – Provider of electrical and mechanical design, construction, and maintenance services to the commercial and industrial markets in various regional markets and nationwide in certain areas of expertise, such as the power infrastructure market and data centers. The words “IES”, the “Company”, “we”, “our”, and “us” refer to IES Holdings, Inc. and, except as otherwise specified herein, to our consolidated subsidiaries.

Summary of Significant Accounting Policies (Notes)

12 Months Ended

Sep. 30, 2020

Accounting Policies [Abstract]

Basis of Presentation and Significant Accounting Policies [Text Block]

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Principles of Consolidation

The accompanying Consolidated Financial Statements include the accounts of IES Holdings, Inc. and its consolidated subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation.

Asset Impairment

At September 30, 2020, we recorded an impairment charge of $6,976 to Goodwill related to our Commercial & industrial segment. Please refer to Note 17, “Goodwill and Intangible Assets” for further discussion. During the fiscal years ended September 30, 2019 and 2018, the Company recorded no asset impairment charges.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires the use of estimates and assumptions by management in determining the reported amounts of assets and liabilities, disclosures of contingent liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Estimates are primarily used in our revenue recognition of construction in progress, fair value assumptions in accounting for business combinations and analyzing goodwill, investments, intangible assets and long-lived asset impairments and adjustments, allowance for doubtful accounts receivable, stock-based compensation, reserves for legal matters, realizability of deferred tax assets, unrecognized tax benefits and self-insured claims liabilities and related reserves.

Cash and Cash Equivalents

We consider all highly liquid investments purchased with an original maturity of three months or less to be cash equivalents.

Inventories

Inventories consist of raw materials, work in process, finished goods, and parts and supplies held for use in the ordinary course of business. Inventory is valued at the lower of cost or net realizable value generally using the historical average cost or first-in, first-out (FIFO) method. When circumstances dictate, we write down inventory to its estimated net realizable value based on assumptions about future demand, market conditions, plans for disposal, and physical condition of the product. Where shipping and handling costs on inventory purchases are borne by us, these charges are included in inventory and charged to cost of services upon use in our projects or the providing of services.

Property and Equipment

Additions of property and equipment are recorded at cost, and depreciation is computed using the straight-line method over the estimated useful life of the related asset. Leasehold improvements are capitalized and depreciated over the lesser of the life of the lease or the estimated useful life of the asset.

Expenditures for repairs and maintenance are charged to expense when incurred. Expenditures for major renewals and betterments, which extend the useful lives of existing property and equipment, are capitalized and depreciated. Upon retirement or disposition of property and equipment, the capitalized cost and related accumulated depreciation are removed from the accounts and any resulting gain or loss is recognized in the statements of comprehensive income in the caption (gain) loss on sale of assets.

Goodwill

Goodwill attributable to each reporting unit is tested for impairment either by comparing the fair value of each reporting unit with its carrying value or by a qualitative assessment. These impairment tests are required to be performed at least annually. On an ongoing basis (absent any impairment indicators), we perform an impairment test annually using a measurement date of September 30. In evaluating goodwill for impairment, we have the option to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is greater than its carrying value. If we determine that it is more likely than not that the carrying value of a reporting unit is greater than its fair value, then we perform an impairment test by calculating the fair value of the reporting unit and comparing this calculated fair value with the carrying value of the reporting unit.

We estimate the fair value of the reporting unit based on both a market approach and an income approach, using discounted estimated future cash flows. The market approach uses market multiples of enterprise value to earnings before interest, taxes, depreciation and amortization for comparable publicly traded companies. The income approach relies on significant estimates for future cash flows, projected long-term growth rates, and the weighted average cost of capital.

Intangible Assets

Intangible assets with definite lives are amortized over their estimated useful lives based on expected economic benefit with no residual value.

Debt Issuance Costs

Debt issuance costs are included as a reduction of our debt outstanding, or alternately classified within other non-current assets if we have no borrowings drawn on our credit facility at the balance sheet date, and are amortized to interest expense over the scheduled maturity of the debt. Amortization expense of debt issuance costs was $152, $318 and $288, respectively, for the years ended 2020, 2019 and 2018. Remaining unamortized capitalized debt issuance costs were $736 and $782 at September 30, 2020, and 2019, respectively.

Revenue Recognition

Revenue is generally recognized from a contract with a customer when: (i) it has approval and commitment from both parties, (ii) the rights of the parties are identified, (iii) payment terms are identified, (iv) the contract has commercial substance, and (v) collectability of consideration is probable. We consider the start of a project to be when the above criteria have been met and we have written authorization from the customer to proceed.

We recognize revenue on project contracts using the percentage of completion method. Project contracts generally provide that customers accept completion of progress to date and compensate us for services rendered measured in terms of units installed, hours expended or some other measure of progress. We recognize revenue on both signed contracts and change orders. A discussion of our treatment of claims and unapproved change orders is described later in this section. Percentage of completion for construction contracts is measured principally by the percentage of costs incurred and accrued to date for each contract to the estimated total cost for each contract at completion. We generally consider contracts to be substantially complete upon departure from the work site and acceptance by the customer. Contract costs include all direct material, labor and insurance costs and those indirect costs related to contract performance, such as indirect labor, supplies, tools, repairs and depreciation costs. Changes in job performance, job

conditions, estimated contract costs and profitability and final contract settlements can result in change orders under which the customer agrees to pay additional contract price. Revisions can also result in claims we might make against the customer to recover additional costs that have not been resolved through change orders with the customer. Except in certain circumstances, we do not recognize revenue or margin based on change orders or claims until they have been agreed upon with the customer. The amount of revenue associated with unapproved change orders and claims was immaterial for the years ended September 30, 2020, 2019 and 2018. Provisions for total estimated losses on uncompleted contracts are made in the period in which such losses are determined. The balances billed but not paid by customers pursuant to retainage provisions in project contracts are typically due upon completion of the contracts and acceptance by the customer. Based on our experience, the retention balance at each balance sheet date will be collected within the subsequent fiscal year.

Certain divisions in the Residential and Infrastructure Solutions segments use the completed contract method of accounting because the duration of their contracts is short in nature. We recognize revenue on completed contracts when the project is complete and billable to the customer. Provisions for estimated losses on these contracts are recorded in the period such losses are determined.

Accounts Receivable and Allowance for Doubtful Accounts

We record accounts receivable for all amounts billed and not collected. Generally, we do not charge interest on outstanding accounts receivable; however, from time to time we may believe it necessary to charge interest on a case by case basis. Additionally, we provide an allowance for doubtful accounts for specific accounts receivable where collection is considered doubtful as well as for general unknown collection issues based on historical trends. Accounts receivable not determined to be collectible are written off as deemed necessary in the period such determination is made. As is common in our industry, some of these receivables are in litigation or require us to exercise our contractual lien rights in order to collect. Our allowance for doubtful accounts at September 30, 2020 and 2019 was $2,613 and $1,184, respectively. We believe that our allowance for doubtful accounts is sufficient to cover uncollectible receivables as of September 30, 2020.

Comprehensive Income (Loss)

Comprehensive income (loss) includes all changes in equity during a period except those resulting from investments by and distributions to stockholders.

Income Taxes

We follow the liability method of accounting for income taxes. Under this method, deferred income tax assets and liabilities are recorded for the future income tax consequences of temporary differences between the financial reporting and income tax bases of assets and liabilities, and are measured using enacted tax rates and laws.

We regularly evaluate valuation allowances established for deferred tax assets for which future realization is uncertain. We perform this evaluation on a quarterly basis. The estimation of required valuation allowances includes estimates of future taxable income. In assessing the realizability of deferred tax assets, we must consider whether it is more likely than not some portion, or all, of the deferred tax assets will not be realized. We consider all available evidence, both positive and negative, in determining whether a valuation allowance is required. At September 30, 2020, we concluded, based upon the assessment of positive and negative evidence, that it is more likely than not that the Company will generate sufficient taxable income within the applicable net operating loss ("NOL") carryforward periods to realize its net deferred tax assets of $33,803. We considered the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies in making this assessment. If actual future taxable income is different from these estimates, our results could be affected.

Risk Management

We retain the risk for workers’ compensation, employer’s liability, automobile liability, construction defects, general liability and employee group health claims, as well as pollution coverage, resulting from uninsured deductibles per accident or occurrence which are generally subject to annual aggregate limits. Our general liability program provides coverage for bodily injury and property damage. In many cases, we insure third parties, including general contractors, as additional insureds under our insurance policies. Losses are accrued based upon our known claims incurred and an estimate of claims incurred but not reported. Each year, we compile our historical data pertaining to the insurance experiences and actuarially develop the ultimate loss associated with our insurance programs other than pollution coverage for our Infrastructure Solutions segment. We believe that the actuarial valuation provides the best estimate of the ultimate losses to be expected under these programs.

The undiscounted ultimate losses of our workers’ compensation, auto and general liability insurance reserves at September 30, 2020, and 2019, was $3,886 and $4,975, respectively. Based on historical payment patterns, we expect payments of undiscounted ultimate losses to be made as follows:


Year Ended September 30:
	2021	$	1,195
	2022		839
	2023		538
	2024		347
	2025		217
	Thereafter		750
Total		$	3,886

We elect to discount the ultimate losses above to present value using an approximate risk-free rate over the average life of our insurance claims. For the years ended September 30, 2020 and 2019, the discount rate used was 0.3 percent and 1.6 percent, respectively. The present value of all insurance reserves for the workers’ compensation, auto and general liability recorded at September 30, 2020, and 2019 was $3,832 and $4,702, respectively. Our undiscounted reserves for employee group health claims at September 30, 2020, and 2019 were $2,422 and $1,981, respectively, and are anticipated to be resolved within the year ended September 30, 2021.

We had letters of credit totaling $5,464 outstanding at September 30, 2020 to collateralize certain of our high deductible insurance obligations.

Realization of Long-Lived Assets

We evaluate the recoverability of property and equipment and other long-lived assets as facts and circumstances indicate that any of those assets might be impaired. If an evaluation is required for our assets we plan to hold and use, the estimated future undiscounted cash flows associated with the asset are compared to the asset’s carrying amount to determine if an impairment of such property has occurred. The effect of any impairment would be to expense the difference between the fair value of such property and its carrying value. Estimated fair values are determined based on expected future cash flows discounted at a rate we believe incorporates the time value of money, the expectations about future cash flows and an appropriate risk premium.

At September 30, 2020, we performed an asset impairment test for all long-lived assets within our Commercial & Industrial segment and determined no impairment charge was necessary. For the years ended September 30, 2019 and 2018, no indicators of impairments were identified, and no impairment charges were recorded.

Risk Concentration

Financial instruments, which potentially subject us to concentrations of credit risk, consist principally of cash deposits and accounts receivable. Through delayed payment terms, we at times grant credit, usually without collateral, to our customers, who are generally large public companies, contractors and homebuilders throughout the United States. Consequently, we are subject to potential credit risk related to changes in business and economic factors throughout the United States, specifically, within the construction, homebuilding and mission critical facility markets. However, we are entitled to payment for work performed and generally have certain lien rights in that work. Further, management believes that its contract acceptance, billing and collection policies are adequate to manage potential credit risk. We routinely maintain cash balances in financial institutions in excess of federally insured limits. We periodically assess the financial condition of these institutions where these funds are held and believe the credit risk is minimal. We maintain the majority of our cash and cash equivalents in money market mutual funds. There can be no assurance, however, that we will not be adversely affected by credit risks we face.

No single customer accounted for more than 10% of our consolidated revenues for the years ended September 30, 2020, 2019 and 2018.

Fair Value of Financial Instruments

Our financial instruments consist of cash and cash equivalents, accounts receivable, accounts payable, and a loan agreement. We believe that the carrying value of financial instruments approximates their fair value due to their short-term nature. The carrying value of our debt approximates fair value, as debt incurs interest at a variable rate.

Stock-Based Compensation

We measure and record compensation expense for all share-based payment awards based on the fair value of the awards granted at the date of grant. The fair value of restricted stock awards and phantom stock unit awards is determined based on the number of shares granted and the closing price of IES’s common stock on the date of grant. For awards vesting upon achievement of a market condition, the likelihood of achieving that market condition is considered in determining the fair value of the grant, which we expense ratably over the vesting period. For awards vesting upon achievement of a performance condition, we record expense based on the grant date fair value when it becomes probable the performance condition will be achieved. Forfeitures are recorded in the period in which they occur. The resulting compensation expense is recognized on a straight-line basis over the requisite service period, which is generally the vesting period.

Deferred Compensation Plans

The Company maintains a rabbi trust to fund certain deferred compensation plans. The securities held by the trust are classified as trading securities. The investments are recorded at fair value and are classified as other non-current assets in the accompanying Consolidated Balance Sheets as of September 30, 2020, and 2019. The changes in fair values are recorded as a component of other income (expense) in the Consolidated Statements of Comprehensive Income (Loss).

The corresponding deferred compensation liability is included in other non-current liabilities on the Consolidated Balance Sheets and changes in this obligation are recognized as adjustments to compensation expense in the period in which they are determined.

Noncontrolling Interest

In connection with our acquisitions of STR Mechanical, LLC (“STR Mechanical”) in fiscal 2016 and NEXT Electric, LLC (“NEXT Electric”) in fiscal 2017, we acquired 80 percent interests in these entities, and the remaining 20 percent was retained by the third party sellers. The interests retained by those third party sellers are identified on our Consolidated Balance Sheets as noncontrolling interest, classified outside of permanent equity. Under the terms of the operating agreements governing these entities, after five years from the dates of the acquisitions, we may elect to purchase, or the third party sellers may require us to purchase, part or all of the remaining 20 percent interests in these entities. The purchase price is variable, based on a multiple of earnings as defined in the operating agreements. Therefore, this noncontrolling interest is carried at the greater of the balance determined under Accounting Standards Codification Topic 810 ("ASC 810") and the redemption amounts assuming the noncontrolling interests were redeemable at the balance sheet date. If all of these interests had been redeemable at September 30, 2020, the redemption amount would have been $1,582. For the year ended September 30, 2020, we recorded a decrease to retained earnings of $194 to increase the carrying amount of noncontrolling interest in NEXT Electric to its redemption amount had it been redeemable at September 30, 2020. For the year ended September 30, 2018, we recorded an increase to retained earnings of $44 to offset an increase to noncontrolling interest recorded in fiscal 2017, decreasing the carrying amount of the noncontrolling interest in STR to the balance determined under ASC 810, as if it had been redeemable at September 30, 2018, as the redemption amount would have been less than the carrying amount.

Leases

We enter into various contractual arrangements for the right to use facilities, vehicles and equipment. We evaluate whether each of these arrangements contains a lease and classify all identified leases as either operating or finance. If the arrangement is subsequently modified, we re-evaluate our classification. The lease term generally ranges from two to ten years for facilities and three to five years for vehicles and equipment. Our lease terms may include the exercise of renewal or termination options when it is reasonably certain these options will be exercised. Our lease agreements do not contain any material residual value guarantees or restrictive covenants.

Upon commencement of the lease, we recognize a lease liability and corresponding right-of use ("ROU") asset for all leases with an initial term greater than twelve months. Lease liabilities represent the present value of our future lease payments over the expected lease term. As most of our leases do not provide an implicit rate, we generally use our incremental borrowing rate as the discount rate in calculating the present value of the lease payments. The incremental borrowing rate is determined by identifying a synthetic credit rating for the consolidated company, where treasury functions are centrally managed, and adjusting the interest rates from associated indexes for differences in credit risk and interest rate risk. We have elected to combine the lease and nonlease components in the recognition of our lease liabilities across all classes of underlying assets. ROU assets represent our right to control the use of the leased asset during the lease and are recognized in an amount equal to the lease liability with adjustments for prepaid or accrued rent, lease incentives or unamortized initial direct costs. Costs associated with operating lease assets are recognized on a straight-line basis over the term of the lease. Our lease assets are tested for impairment in the same manner as long-lived assets used in operations.

Certain lease contracts include obligations to pay for other services, such as operations and maintenance. Where the costs of these services can be identified as fixed or fixed-in-substance, the costs are included as part of the future lease payments. If the cost is not fixed at the inception of the lease, the cost is recorded as a variable cost in the period incurred.

Accounting Standards Not Yet Adopted

In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standard Update No. 2016-13, Financial Instruments – Credit Losses (“ASU 2016-13”), which requires companies to consider historical experiences, current market conditions and reasonable and supportable forecasts in the measurement of expected credit losses, with further clarifications made in April 2019 and May 2019 with the issuances of Accounting Standard Updates No. 2019-04 and 2019-05. This update is effective for fiscal years beginning after December 15, 2019 and for interim periods within those fiscal years, although early adoption is permitted. We plan to adopt this standard on October 1, 2020, and do not expect the adoption to have a material effect on our Consolidated Financial Statements.

In August 2018, the FASB issued Accounting Standard Update No. 2018-13, Fair Value Measurement Disclosure Framework (“ASU 2018-13”), to modify certain disclosure requirements for fair value measurements. Under the new guidance, registrants will need to disclose weighted average information for significant unobservable inputs for all Level 3 fair value measurements. The guidance does not specify how entities should calculate the weighted average, but requires them to explain their calculation. The new guidance also requires disclosing the changes in unrealized gains and losses for the period included in other comprehensive income for recurring Level 3 fair value measurements of instruments held at the end of the reporting period. This guidance is effective for fiscal years beginning after December 15, 2019 and for interim periods within those fiscal years, although early adoption is permitted for either the entire standard or only the provisions that eliminate or modify the requirements. We plan to adopt this standard on October 1, 2020, and do not expect the adoption to have a material effect on our Consolidated Financial Statements.

Accounting Standards Recently Adopted

In February 2016, the FASB issued Accounting Standard Update No. 2016-02, Leases (“ASU 2016-02”). Under ASU 2016-02, lessees need to recognize a ROU asset and a lease liability on their balance sheets for all leases, other than those that meet the definition of a short-term lease. For income statement purposes, leases must be classified as either operating or finance. Operating leases result in straight-line expense, while finance leases are accounted for similar to capital leases under the previous lease accounting standard. We adopted ASU 2016-02 on October 1, 2019 using a modified retrospective transition approach. Using the optional transition method allowed under Accounting Standard Update No. 2018-11, prior period amounts were not adjusted retrospectively and continue to be reported using the previous accounting standards in effect for the period presented. We elected to utilize all of the available practical expedients with the exception of the practical expedient permitting the use of hindsight when determining the lease term and assessing impairment of ROU assets. Therefore, we did not reassess whether any of our existing or expired contracts contained leases or the classification of or initial direct costs included in our existing or expired leases.

The adoption of ASU 2016-02 resulted in the recognition of ROU assets of approximately $32,434 and operating lease liabilities of approximately $32,237 on our Consolidated Balance Sheets at the adoption date. The difference between the ROU assets and lease liabilities was primarily due to previously accrued rent expense relating to periods prior to October 1, 2019. The adoption did not have a significant impact on our Consolidated Statements of Comprehensive Income or Cash Flows. See Note 9, “Leases” for additional discussion of our lease accounting policies and expanded disclosures.

In June 2018, the FASB issued Accounting Standard Update No. 2018-07, Compensation—Stock Compensation (“ASU 2018-07”), to simplify the accounting for share-based payments to nonemployees by aligning it with the accounting for share-based payments for employees, with certain exceptions. Under the new guidance, the cost for nonemployee awards may be lower and less volatile than under current GAAP because the measurement generally will occur earlier and will be fixed at the grant date. This update was adopted as of October 1, 2019 with no impact to our financial statements.

Controlling Shareholder	12 Months Ended
Controlling Shareholder	Sep. 30, 2020
Risks and Uncertainties [Abstract]
Controlling Shareholder [Text Block]	3. CONTROLLING SHAREHOLDER Tontine Associates, L.L.C. ("Tontine Associates"), together with its affiliates (collectively, "Tontine") is the Company's controlling shareholder, owning approximately 56 percent of the Company’s outstanding common stock based on an amended Schedule 13D filed with the SEC by Tontine on October 9, 2020. Accordingly, Tontine has the ability to exercise significant control over our affairs, including the election of directors and most actions requiring the approval of shareholders. While Tontine is subject to certain restrictions under federal securities laws on sales of its shares as an affiliate, the Company has filed a shelf registration statement to register all of the shares of IES common stock owned by Tontine at the time of registration. As long as the shelf registration statement remains effective and the Company remains eligible to use it, Tontine has the ability to resell any or all of its registered shares from time to time in one or more offerings, as described in the shelf registration statement and in any prospectus supplement filed in connection with an offering pursuant to the shelf registration statement. Should Tontine sell or otherwise dispose of all or a portion of its position in IES, a change in ownership of IES could occur. A change in ownership, as defined by Internal Revenue Code Section 382, could reduce the availability of the Company’s NOLs for federal and state income tax purposes. On November 8, 2016, the Company implemented a tax benefit protection plan (the “NOL Rights Plan”). The NOL Rights Plan is designed to deter an acquisition of the Company's stock in excess of a threshold amount that could trigger a change in ownership within the meaning of Internal Revenue Code Section 382. There can be no assurance that the NOL Rights Plan will be effective in deterring a change in ownership or protecting the NOLs. Furthermore, a change of control would trigger the change of control provisions in a number of our material agreements, including our credit agreement, bonding agreements with our sureties and our executive severance plan. Jeffrey L. Gendell was appointed as Chief Executive Officer of the Company effective October 1, 2020, having served as the Company's Interim Chief Executive Officer since July 31, 2020. Mr. Gendell also serves as Chairman of the Board of Directors, a position he has held since November 2016. He is the managing member and founder of Tontine, and the brother of David B. Gendell, who has served as a member of our Board of Directors since February 2012, and who previously served as Interim Director of Operations from November 2017 to January 2019, as Vice Chairman of the Board from November 2016 to November 2017 and as Chairman of the Board from January 2015 to November 2016. David B. Gendell was an employee of Tontine from 2004 until December 31, 2017. The Company is party to a sublease agreement with Tontine Associates for corporate office space in Greenwich, Connecticut. The sublease extends through February 27, 2023, with monthly payments due in the amount of approximately $8. Payments by the Company are at a rate consistent with that paid by Tontine Associates to its landlord. On December 6, 2018, the Company entered into a Board Observer Letter Agreement (the "Observer Agreement") with Tontine Associates, in order to assist Tontine in managing its investment in the Company. Subject to the terms and conditions set forth in the Observer Agreement, the Company granted Tontine the right, at any time that Tontine holds at least 20% of the outstanding common stock of the Company, to appoint a representative to serve as an observer to the Board (the “Board Observer”). The Board Observer, who must be reasonably acceptable to those members of the Board who are not affiliates of Tontine, shall have no voting rights or other decision making authority. Subject to the terms and conditions set forth in the Observer Agreement, so long as Tontine has the right to appoint a Board Observer, the Board Observer will have the right to attend and participate in meetings of the Board and the committees thereof, subject to confidentiality requirements, and to receive reimbursement for reasonable out-of-pocket expenses incurred in his or her capacity as a Board Observer and such rights to coverage under the Company’s directors’ and officers’ liability insurance policy as are available to the Company’s directors.

Revenue Recognition

12 Months Ended

Sep. 30, 2020

Revenue Recognition and Deferred Revenue [Abstract]

Revenue from External Customers by Products and Services [Table Text Block]

4. REVENUE RECOGNITION

Contracts

Our revenue is derived from contracts with customers, and we determine the appropriate accounting treatment for each contract at its inception. Our contracts primarily relate to electrical and mechanical contracting services, technology infrastructure products and services, and electro-mechanical solutions for industrial operations. Revenue is earned based upon an agreed fixed price or actual costs incurred plus an agreed upon percentage.

We account for a contract when: (i) it has approval and commitment from both parties, (ii) the rights of the parties are identified, (iii) payment terms are identified, (iv) the contract has commercial substance, and (v) collectability of consideration is probable. We consider the start of a project to be when the above criteria have been met and we have written authorization from the customer to proceed.

Performance Obligations

A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied.

We recognize revenue over time for the majority of the services we perform as (i) control continuously transfers to the customer as work progresses at a project location controlled by the customer and (ii) we have the right to bill the customer as costs are incurred. Within our Infrastructure Solutions segment, we often perform work inside our own facilities, where control does not continuously transfer to the customer as work progresses. In such cases, we evaluate whether we have the right to bill the customer as costs are incurred. Such assessment involves an evaluation of contractual termination clauses. Where we have a contractual right to payment for work performed to date, we recognize revenue over time. If we do not have such a right, we recognize revenue upon completion of the contract, when control of the work transfers to the customer.

For fixed price arrangements, we use the percentage of completion method of accounting under which revenue recognized is measured principally by the costs incurred and accrued to date for each contract as a percentage of the estimated total cost for each contract at completion. Contract costs include all direct material, labor and indirect costs related to contract performance. Changes in job

performance, job conditions, estimated contract costs and profitability and final contract settlements may result in revisions to costs and income, and the effects of these revisions are recognized in the period in which the revisions are determined. Provisions for estimated losses on uncompleted contracts are made in the period in which such losses are determined. This measurement and comparison process requires updates to the estimate of total costs to complete the contract, and these updates may include subjective assessments and judgments.

Variable Consideration

The transaction price for our contracts may include variable consideration, which includes changes to transaction price for approved and unapproved change orders, claims and incentives. Change orders, claims and incentives are generally not distinct from the existing contract due to the significant integration service provided in the context of the contract and are accounted for as a modification of the existing contract and performance obligation. We estimate variable consideration for a performance obligation at the probability weighted value we expect to receive (or the most probable amount we expect to incur in the case of liquidated damages, if any), utilizing estimation methods that best predict the amount of consideration to which we will be entitled (or will be incurred in the case of liquidated damages, if any). We include variable consideration in the estimated transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur or when the uncertainty associated with the variable consideration is resolved. Our estimates of variable consideration and determination of whether to include estimated amounts in transaction price are based largely on an assessment of our anticipated performance and all information (historical, current and forecasted) that is reasonably available to us. The effect of variable consideration on the transaction price of a performance obligation is recognized as an adjustment to revenue on a cumulative catch-up basis. To the extent unapproved change orders and claims reflected in transaction price (or accounted for as a reduction of the transaction price in the case of liquidated damages) are not resolved in our favor, or to the extent incentives reflected in transaction price are not earned, there could be reductions in, or reversals of, previously recognized revenue.

Costs of Obtaining a Contract

In certain of our operations, we incur commission costs related to entering into a contract that we only incurred because of that contract. When this occurs, we capitalize that cost and amortize it over the expected term of the contract. At September 30, 2020, we had capitalized commission costs of $94.

We generally do not incur significant incremental costs related to obtaining or fulfilling a contract prior to the start of a project. When significant pre‑contract costs are incurred, they will be capitalized and amortized on a percentage of completion basis over the life of the contract.

Disaggregation of Revenue

We disaggregate our revenue from contracts with customers by activity and contract type, as these categories reflect how the nature, amount, timing and uncertainty of our revenue and cash flows are affected by economic factors. Our consolidated 2020, 2019, and 2018 revenue was derived from the following activities. See details in the following tables:


	Year Ended September 30,
	2020		2019		2018
Communications	$	395,141	$	321,246	$	219,655
Residential
Single-family	239,140		212,358		190,379
Multi-family and Other	172,650		100,978		95,332
Total Residential	411,790		313,336		285,711
Infrastructure Solutions
Industrial Services	40,701		48,948		44,701
Custom Power Solutions	87,678		87,842		52,462
Total Infrastructure Solutions	128,379		136,790		97,163
Commercial & Industrial	255,546		305,624		274,299
Total Revenue	$	1,190,856	$	1,076,996	$	876,828


	Year Ended September 30, 2020
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Total
Fixed-price		$	309,567	$	411,790	$	121,922	$	241,864	$	1,085,143
Time-and-material		85,574		—		6,457		13,682		105,713
Total revenue		$	395,141	$	411,790	$	128,379	$	255,546	$	1,190,856


	Year Ended September 30, 2019
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Total
Fixed-price		$	229,143	$	313,336	$	129,096	$	286,319	$	957,894
Time-and-material		92,103		—		7,694		19,305		119,102
Total revenue		$	321,246	$	313,336	$	136,790	$	305,624	$	1,076,996

	Year Ended September 30, 2018
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Total
Fixed-price		$	166,258	$	285,711	$	90,155	$	244,464	$	786,588
Time-and-material		53,397		—		7,008		29,835		90,240
Total revenue		$	219,655	$	285,711	$	97,163	$	274,299	$	876,828

Accounts Receivable

Accounts receivable include amounts which we have billed or have an unconditional right to bill our customers. As of September 30, 2020, Accounts receivable included $10,710 of unbilled receivables for which we have an unconditional right to bill.

Contract Assets and Liabilities

Project contracts typically provide for a schedule of billings on percentage of completion of specific tasks inherent in the fulfillment of our performance obligation(s). The schedules for such billings usually do not precisely match the schedule on which costs are incurred. As a result, contract revenue recognized in the statement of operations can and usually does differ from amounts that can be billed to the customer at any point during the contract. Amounts by which cumulative contract revenue recognized on a contract as of a given date exceeds cumulative billings and unbilled receivables to the customer under the contract are reflected as a current asset in our Consolidated Balance Sheets under the caption “Costs and estimated earnings in excess of billings”. Amounts by which cumulative billings to the customer under a contract as of a given date exceed cumulative contract revenue recognized are reflected as a current liability in our Consolidated Balance Sheets under the caption “Billings in excess of costs and estimated earnings”.

During the years ended September 30, 2020, and 2019, we recognized revenue of $34,035 and $31,831 related to our contract liabilities at October 1, 2019 and 2018, respectively.

We did not have any impairment losses recognized on our receivables or contract assets for the years ended September 30, 2020, 2019, or 2018.

Remaining Performance Obligations

Remaining performance obligations represent the unrecognized revenue value of our contract commitments. New awards represent the total expected revenue value of new contract commitments undertaken during a given period, as well as additions to the scope of existing contract commitments. Our new performance obligations vary significantly each reporting period based on the timing of our major new contract commitments. At September 30, 2020, we had remaining performance obligations of $505,352. The Company expects to recognize revenue on approximately $438,253 of the remaining performance obligations over the next 12 months, with the remaining recognized thereafter.

For the year ended September 30, 2020, net revenue recognized from our performance obligations satisfied in previous periods was not material.

Property and Equipment (Notes)

12 Months Ended

Sep. 30, 2020

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment Disclosure [Text Block]

5. PROPERTY AND EQUIPMENT

Property and equipment consists of the following:


	Estimated Useful Lives in Years			Year Ended September 30,
				2020		2019
Land	N/A			$	1,436	$	1,436
Buildings and improvements	5	-	20	14,378		13,608
Machinery and equipment	3	-	10	32,695		30,600
Information systems	2	-	8	8,496		7,945
Furniture and fixtures	5	-	7	1,746		1,587
				$	58,751	$	55,176
Less-Accumulated depreciation				(34,544)		(29,560)
Construction in progress				382		130
Property and equipment, net				$	24,589	$	25,746

Depreciation expense was $6,084, $5,607 and $4,759, respectively, for the years ended September 30, 2020, 2019 and 2018.

Per Share Information

12 Months Ended

Sep. 30, 2020

Earnings Per Share [Abstract]

Earnings Per Share [Text Block]

6. PER SHARE INFORMATION

Basic earnings per share is calculated as income (loss) available to common stockholders, divided by the weighted average number of common shares outstanding during the period. If the effect is dilutive, participating securities are included in the computation of basic earnings per share. Our participating securities do not have a contractual obligation to share in the losses in any given period. As a result, these participating securities will not be allocated any losses in the periods of net losses, but will be allocated income in the periods of net income using the two-class method.

The following table reconciles the components of the basic and diluted earnings (loss) per share for the years ended September 30, 2020, 2019 and 2018:


	Year Ended September 30,
	2020		2019		2018
Numerator:
Net income (loss) attributable to common shareholders of IES Holdings, Inc.	$	40,830	$	32,950	$	(14,113)
Increase (decrease) in noncontrolling interest	194		—		(44)
Net income attributable to restricted shareholders of IES Holdings, Inc.	575		256		—
Net income (loss) attributable to IES Holdings, Inc.	$	41,599	$	33,206	$	(14,157)

Denominator:
Weighted average common shares outstanding — basic	20,795,892		21,082,012		21,196,388
Effect of dilutive stock options and non-vested securities	296,518		233,233		—
Weighted average common and common equivalent shares outstanding — diluted	21,092,410		21,315,245		21,196,388

Earnings (loss) per share attributable to common shareholders of IES Holdings, Inc.:
Basic	$	1.96	$	1.56	$	(0.67)
Diluted	$	1.94	$	1.55	$	(0.67)

For the years ended September 30, 2020 and September 30, 2019, the average price of our common shares exceeded the exercise price of outstanding options; therefore, outstanding stock options were included in the computation of diluted earnings per share.

When an entity has a net loss, it is prohibited from including potential common shares in the computation of diluted per share amounts. Accordingly, we have utilized basic shares outstanding to calculate both basic and diluted loss per share for the year ended

September 30, 2018. The number of potential anti-dilutive shares excluded from the calculation was 301,879 shares for the year ended September 30, 2018.

Detail of Certain Balance Sheet Accounts (Notes)

12 Months Ended

Sep. 30, 2020

Detail of Certain Balance Sheet Accounts [Abstract]

Detail Of Certain Balance Sheet Accounts [Text Block]

7. DETAIL OF CERTAIN BALANCE SHEET ACCOUNTS

Activity in our allowance for doubtful accounts on accounts receivable consists of the following:


	Year Ended September 30,
	2020		2019
Balance at beginning of period	$	1,184	$	868
Additions to costs and expenses	1,864		552
Deductions for uncollectible receivables written off, net of recoveries	(435)		(236)
Balance at end of period	$	2,613	$	1,184

Accounts payable and accrued expenses consist of the following:


	Year Ended September 30,
	2020		2019
Accounts payable, trade	$	93,315	$	85,276
Accrued compensation and benefits	53,933		42,828
Accrued insurance liabilities	6,254		6,683
Current operating lease liabilities	11,056		—
Other accrued expenses	22,152		18,122
	$	186,710	$	152,909

Other non-current assets are comprised of the following:


	Year Ended September 30,
	2020		2019
Executive Savings Plan assets	$	766	$	763
Securities and equity investments	—		408
Other	5,014		3,767
Total	$	5,780	$	4,938

Debt

12 Months Ended

Sep. 30, 2020

Debt Disclosure [Abstract]

Debt Disclosure [Text Block]

8. DEBT

Debt consists of the following:


	Year Ended September 30,
	2020		2019
Revolving loan (long-term debt)	$	12	$	—
Debt issuance costs (1)	—		—
Other long-term debt	205		299
Total debt	$	217	$	299

(1) At September 30, 2020 and 2019, the remaining unamortized debt issuance costs of $736 and $782, respectively, were reclassified to Other non-current assets on the Consolidated Balance Sheets.

At September 30, 2020, we had outstanding borrowings of $12, $5,664 in outstanding letters of credit and $94,324 of availability under our revolving credit facility with Wells Fargo Bank, N.A. ("Wells Fargo"). All amounts outstanding under our revolving credit facility are due and payable in September 2024, upon expiration of our revolving credit facility, and all amounts described as available are available without triggering our financial covenant under the Amended Credit Agreement (as defined below).

Our interest rate on our outstanding borrowings under our revolving credit facility was 1.48% at September 30, 2020. For the years ended September 30, 2020, 2019 and 2018, we incurred interest expense of $777, $1,857 and $1,946, respectively.

The Revolving Credit Facility

We maintain a $100,000 revolving credit facility that matures on September 30, 2024 pursuant to a credit agreement with Wells Fargo (as amended, the “Amended Credit Agreement”).

Terms of the Amended Credit Agreement

The Amended Credit Agreement contains customary affirmative, negative and financial covenants, as well as customary events of default.

As of September 30, 2020, we were in compliance with the financial covenants under the Amended Credit Agreement, requiring that we maintain:

• a Fixed Charge Coverage Ratio (as defined in the Amended Credit Agreement), measured quarterly on a trailing four-quarter basis at the end of each quarter, of at least 1.1 to 1.0; and

• minimum Liquidity (as defined in the Amended Credit Agreement) of at least twenty percent (20%) of the Maximum Revolver Amount (as defined in the Amended Credit Agreement), or $20,000; with, for purposes of this covenant, at least fifty percent (50%) of our Liquidity comprised of Excess Availability (as defined in the Amended Credit Agreement).

At September 30, 2020, our Liquidity was $147,902 and our Excess Availability was $94,324 (or greater than 50% of minimum Liquidity), our Fixed Charge Coverage Ratio was 8.3:1.0.

Our Fixed Charge Coverage Ratio is calculated as follows (with capitalized terms as defined in the Amended Credit Agreement): (i) our trailing twelve month EBITDA, less Non-Financed Capital Expenditures (other than capital expenditures financed by means of an advance under the credit facility), cash taxes and all Restricted Junior Payments (as defined in the Amended Credit Agreement) consisting of certain Pass-Through Tax Liabilities (as defined in the Amended Credit Agreement), divided by (ii) the sum of our cash interest (other than interest paid-in-kind, amortization of financing fees, and other non-cash interest expense) and principal debt payments (other than repayment of principal on advances under the credit facility and including cash payments with respect to capital leases), any management, consulting, monitoring, and advisory fees paid to an affiliate, and all Restricted Junior Payments (other than Pass-Through Tax Liabilities) and other cash distributions; provided, that if we make an acquisition consented to by Wells Fargo, the components of the Fixed Charge Coverage Ratio will be calculated for such fiscal period after giving pro forma effect to the acquisition assuming that such transaction has occurred on the first day of such period (including pro forma adjustments arising out of events which are directly attributable to such acquisition, are factually supportable, and are expected to have a continuing impact, in each case to be reasonably agreed to by Wells Fargo).

As defined in the Amended Credit Agreement, EBITDA is calculated as consolidated net income (or loss), less extraordinary gains, interest income, non-operating income and income tax benefits and decreases in any change in LIFO reserves, plus stock compensation expense, non-cash extraordinary losses (including, but not limited to, a non-cash impairment charge or write-down), Interest Expense, income taxes, depreciation and amortization, and increases in any change in LIFO reserves for such period, determined on a consolidated basis in accordance with GAAP.

If in the future our Liquidity falls below $20,000 (or Excess Availability falls below 50% of our minimum Liquidity), our Fixed Charge Coverage Ratio is less than 1.1:1.0, or if we otherwise fail to perform or otherwise comply with certain of our covenants or other agreements under the Amended Credit Agreement, it would result in an event of default under the Amended Credit Agreement, which could result in some or all of any indebtedness we may take on becoming immediately due and payable.

Leases (Notes)

12 Months Ended

Sep. 30, 2020

Leases [Abstract]

Leases of Lessee Disclosure [Text Block]

9. LEASES

We enter into various contractual arrangements for the right to use facilities, vehicles and equipment. The lease term generally ranges from two to ten years for facilities and three to five years for vehicles and equipment. Our lease terms may include the exercise of renewal or termination options when it is reasonably certain these options will be exercised. Our lease agreements do not contain any material residual value guarantees or restrictive covenants.

Current operating and finance liabilities of $11,056 and $418, respectively, were included in "Accounts payable and accrued expenses" in the Consolidated Balance Sheets as of September 30, 2020. Non-current finance lease liabilities and finance lease right-of-use assets were included in the "Other non-current liabilities" and "Other non-current assets", respectively, in the Consolidated Balance Sheets.

The maturities of our lease liabilities as of September 30, 2020, are as follows:


	Operating Leases		Finance Leases		Total
2021	$	11,269	$	430	$	11,699
2022	8,743		403		9,146
2023	5,822		401		6,223
2024	3,488		368		3,856
2025	2,110		167		2,277
Thereafter	3,175		—		3,175
Total undiscounted lease payments	$	34,607	$	1,769	$	36,376
Less: imputed interest	3,021		182		3,203
Present value of lease liabilities	$	31,586	$	1,587	$	33,173

The total future undiscounted cash flows related to lease agreements committed to but not yet commenced as of September 30, 2020, is $3,946.

Lease cost recognized in our Consolidated Statements of Comprehensive Income is summarized as follows:


	Year Ended
	September 30, 2020
Operating lease cost	$	12,910
Finance lease cost
Amortization of lease assets	203
Interest on lease liabilities	47
Finance lease cost	250
Short-term lease cost	1,163
Variable lease cost	827
Total lease cost	$	15,150

Other information about lease amounts recognized in our Consolidated Financial Statements is summarized as follows:


	Year Ended
	September 30, 2020
Operating cash flows used for operating leases	$	12,934
Operating cash flows used for finance leases	47
Right-of-use assets obtained in exchange for new operating lease liabilities	10,640
Right-of-use assets obtained in exchange for new finance lease liabilities	1,803


	September 30, 2020
Weighted-average remaining lease term - operating leases	4.3 years
Weighted-average remaining lease term - finance leases	4.4 years
Weighted-average discount rate - operating leases	3.9	%
Weighted-average discount rate - finance leases	5.1	%

For a discussion of leases with certain related parties which are included below, see Note 13, “Related-Party Transactions.”

Rent expense was $14,073, $10,553 and $7,680 for the years ended September 30, 2020, 2019 and 2018, respectively.

Income Taxes (Notes)

12 Months Ended

Sep. 30, 2020

Income Tax Disclosure [Abstract]

Income Tax Disclosure [Text Block]

10. INCOME TAXES

Federal and state income tax provisions are as follows:


	Year Ended September 30,
	2020		2019		2018
Federal:
Current	$	(39)	$	(1,330)	$	(2,345)
Deferred	9,317		5,908		38,744
State:
Current	3,657		2,312		1,536
Deferred	(4,195)		(227)		216
Total provision for income taxes	$	8,740	$	6,663	$	38,151

Actual income tax expense differs from income tax expense computed by applying the U.S. federal statutory corporate rate to income (loss) before income taxes as follows:


	Year Ended September 30,
	2020		2019		2018
Provision at the statutory rate (1)	$	10,352	$	8,430	$	5,973
Increase resulting from:
Non-deductible expenses	1,974		1,277		1,241
State income taxes, net of federal deduction	2,662		2,009		1,193
Change in valuation allowance	—		—		1,761
Rate change	—		—		31,333
Other	261		—		183
Decrease resulting from:
Share-based compensation	(75)		(556)		(238)
Change in valuation allowance	(3,334)		(83)		—
Contingent tax liabilities	(1,313)		(3,967)		(1,908)
Component 2 goodwill utilization	(1,787)		(144)		—
State deferred true up	—		—		(1,387)
Other	—		(303)		—
Total provision for income taxes	$	8,740	$	6,663	$	38,151

(1) A statutory rate of 21% was used in 2020, 21% in 2019 and 24.53% in 2018. The lower effective tax rate used in 2020 and 2019 is related to the Tax Cuts and Jobs Act enacted on December 22, 2017.

Deferred income tax provisions result from temporary differences in the recognition of income and expenses for financial reporting purposes and for income tax purposes. The income tax effects of these temporary differences, representing deferred income tax assets and liabilities, result principally from the following:


	Year Ended September 30,
	2020		2019
Deferred income tax assets:
Allowance for doubtful accounts	$	592	$	245
Accrued expenses	14,619		9,783
Net operating loss carryforward	22,623		39,045
Various reserves	1,764		1,396
Equity losses in affiliate	210		119
Share-based compensation	897		672
Capital loss carryforward	74		74
Lease asset	7,681		—
Other	2,444		1,137
Subtotal	50,904		52,471
Less valuation allowance	710		4,044
Total deferred income tax assets	50,194		48,427
Deferred income tax liabilities:
Property and equipment	517		840
Intangible assets	7,926		5,978
Lease liability	7,677		—
Other	271		735
Total deferred income tax liabilities	16,391		7,553
Net deferred income tax assets	$	33,803	$	40,874

In fiscal 2020 and 2019, the valuation allowance on our deferred tax assets decreased by $3,334 and $83, respectively, which is included in “Provision (benefit) for income taxes” in our Consolidated Comprehensive Income Statement.

As of September 30, 2020, we had available approximately $217,328 of federal net tax operating loss carry forward for federal income tax purposes, including $128,044 from net operating losses on which no tax benefit has been recognized and has not been recorded as a deferred tax asset. This carry forward, which may provide future tax benefits, will begin to expire in 2027. As of September 30, 2020, we had available approximately $76,055 state net tax operating loss carry forwards, including $6,696 from net operating losses on which no tax benefit has been recognized and has not been recorded as a deferred tax asset. The carry forwards, which may provide future tax benefits, will begin to expire in 2021. We have provided valuation allowances on all net operating losses where it is determined it is more likely than not that they will expire without being utilized.

In assessing the realizability of deferred tax assets at September 30, 2020, we considered whether it was more likely than not that some portion or all of the deferred tax assets will not be realized. Our realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which these temporary differences become deductible. As a result, we have recorded a net deferred tax asset of $33,803 on our Consolidated Balance Sheets. We will continue to evaluate the appropriateness of our remaining deferred tax assets and need for valuation allowances on a quarterly basis. Further, any future reduction in the federal statutory tax rate could result in a charge to reduce the book value of the net deferred tax assets recorded on our Consolidated Balance Sheets.

As a result of a 2006 reorganization and related adjustment to the book basis in goodwill, we have tax basis in excess of book basis in amortizable goodwill of approximately $14,539. The tax basis in amortizable goodwill in excess of book basis is not reflected as a deferred tax asset. To the extent the amortization of the excess tax basis results in a cash tax benefit, the benefit will first go to reduce goodwill, then other long-term intangible assets, and then tax expense.

GAAP requires financial statement reporting of the expected future tax consequences of uncertain tax return reporting positions on the presumption that all relevant tax authorities possess full knowledge of those tax reporting positions, as well as all of the pertinent facts and circumstances, but it prohibits discounting of any of the related tax effects for the time value of money. The evaluation of a tax position is a two-step process. The first step is the recognition process to determine if it is more likely than not that a tax position will be sustained upon examination by the appropriate taxing authority, based on the technical merits of the position. The second step is a measurement process whereby a tax position that meets the more likely than not recognition threshold is calculated to determine the amount of benefit/expense to recognize in the financial statements. The tax position is measured at the largest amount of benefit/expense that is more likely than not of being realized upon ultimate settlement.

A reconciliation of the beginning and ending balances of unrecognized tax benefit is as follows:


	Year Ended September 30,
	2020		2019
Balance at beginning of period	$	26,294	$	30,256
Additions for position related to current year	111		93
Additions for positions of prior years	29		19
Reduction resulting from the lapse of the applicable statutes of limitations	1,573		4,074


Balance at end of period	$	24,861	$	26,294

As of September 30, 2020, and 2019, $24,861 and $26,294, respectively, of unrecognized tax benefits would result in a decrease in the provision for income tax expense. We anticipate that approximately $3,061 in liabilities for unrecognized tax benefits, including accrued interest, primarily from net operating losses on which no tax benefit has been recognized, may be reversed in the next twelve months. The reversal is predominately due to the expiration of the statutes of limitation for unrecognized tax benefits.

We had approximately $55 and $43 accrued for the payment of interest and penalties at September 30, 2020, and 2019, respectively. We recognize interest and penalties related to unrecognized tax benefits as part of the provision for income taxes.

The tax years ended September 30, 2017, and forward are subject to federal audit as are tax years prior to September 30, 2017, to the extent of unutilized net operating losses generated in those years. The tax years ended September 30, 2017, and forward are subject to state audits as are tax years prior to September 30, 2017, to the extent of unutilized net operating losses generated in those years.

Operating Segments

12 Months Ended

Sep. 30, 2020

Segment Reporting [Abstract]

Segment Reporting Disclosure [Text Block]

11. OPERATING SEGMENTS

We manage and measure performance of our business in four distinct operating segments: Commercial & Industrial, Communications, Infrastructure Solutions and Residential. These segments are reflective of how the Company’s Chief Operating Decision Maker (“CODM”) reviews operating results for the purposes of allocating resources and assessing performance. The Company’s CODM is its Chief Executive Officer.

Transactions between segments, if any, are eliminated in consolidation. Our corporate office provides general and administrative services, as well as support services, to our four operating segments. Management allocates certain shared costs between segments for selling, general and administrative expenses and depreciation expense.

Segment information for the years ended September 30, 2020, 2019 and 2018 is as follows:


		Year Ended September 30, 2020
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Corporate		Total
Revenues		$	395,141	$	411,790	$	128,379	$	255,546	$	—	$	1,190,856
Cost of services		317,013		318,034		93,358		234,492		—		962,897
Gross profit		78,128		93,756		35,021		21,054		—		227,959
Selling, general and administrative		37,674		63,668		20,418		32,128		17,023		170,911
Goodwill impairment expense		—		—		—		6,976		—		6,976
Contingent consideration		—		—		—		(11)		—		(11)
Loss (gain) on sale of assets		8		2		35		(45)		—		—
Income (loss) from operations		$	40,446	$	30,086	$	14,568	$	(17,994)	$	(17,023)	$	50,083
Other data:
	Depreciation and amortization expense	$	1,351	$	2,276	$	6,020	$	2,768	$	93	$	12,508
	Capital expenditures	$	830	$	1,459	$	795	$	1,362	$	299	$	4,745
	Total assets	$	154,808	$	110,998	$	124,640	$	68,318	$	101,764	$	560,528


		Year Ended September 30, 2019
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Corporate		Total
Revenues		$	321,246	$	313,336	$	136,790	$	305,624	$	—	$	1,076,996
Cost of services		264,746		248,562		105,863		275,722		—		894,893
Gross profit		56,500		64,774		30,927		29,902		—		182,103
Selling, general and administrative		31,850		46,864		18,664		27,815		15,382		140,575
Contingent consideration		(97)		—		(277)		—		—		(374)
Loss (gain) on sale of assets		(6)		(17)		105		(30)		—		52
Income (loss) from operations		$	24,753	$	17,927	$	12,435	$	2,117	$	(15,382)	$	41,850
Other data:
	Depreciation and amortization expense	$	1,513	$	852	$	4,528	$	2,563	$	101	$	9,557
	Capital expenditures	$	973	$	1,412	$	1,377	$	2,402	$	136	$	6,300
	Total assets	$	109,263	$	63,903	$	116,867	$	82,050	$	73,175	$	445,258


		Year Ended September 30, 2018
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Corporate		Total
Revenues		$	219,655	$	285,711	$	97,163	$	274,299	$	—	$	876,828
Cost of services		179,518		227,355		75,337		244,656		—		726,866
Gross profit		40,137		58,356		21,826		29,643		—		149,962
Selling, general and administrative		26,003		41,401		18,293		27,031		11,192		123,920
Contingent consideration		(85)		—		288		(100)		—		103
Loss (gain) on sale of assets		(4)		8		18		(37)		—		(15)
Income (loss) from operations		$	14,223	$	16,947	$	3,227	$	2,749	$	(11,192)	$	25,954
Other data:
	Depreciation and amortization expense	$	1,247	$	637	$	4,672	$	2,197	$	107	$	8,860
	Capital expenditures	$	647	$	932	$	735	$	2,216	$	33	$	4,563
	Total assets	$	80,528	$	55,176	$	109,506	$	89,729	$	87,055	$	421,994

Stockholders' Equity

12 Months Ended

Sep. 30, 2020

Equity [Abstract]

Stockholders' Equity Note Disclosure

12. STOCKHOLDERS’ EQUITY

Equity Incentive Plan

The Company’s 2006 Equity Incentive Plan, as amended and restated (the “Equity Incentive Plan”), provides for grants of stock options as well as grants of stock, including restricted stock. Approximately 3.0 million shares of common stock are authorized for issuance under the Equity Incentive Plan, of which approximately 928,669 shares were available for issuance at September 30, 2020.

Stock Repurchase Program

In 2015, our Board of Directors authorized a stock repurchase program for the purchase from time to time of up to 1.5 million shares of the Company’s common stock, and on May 2, 2019, authorized the repurchase from time to time of up to an additional 1.0 million shares of our common stock under the stock repurchase program. Share purchases are made for cash in open market transactions at prevailing market prices or in privately negotiated transactions or otherwise. The timing and amount of purchases under the program are determined based upon prevailing market conditions, our liquidity requirements, contractual restrictions and other factors. All or part of the repurchases may be implemented under a Rule 10b5-1 trading plan, which allows repurchases under pre-set terms at times when the Company might otherwise be prevented from purchasing under insider trading laws or because of self-imposed blackout periods. The program does not require the Company to purchase any specific number of shares and may be modified, suspended or reinstated at any time at the Company’s discretion and without notice.

We repurchased 263,160 shares of our common stock during the year ended September 30, 2020, in open market transactions at an average price of $23.29 per share.

We repurchased 467,819 shares of our common stock during the year ended September 30, 2019, in open market transactions at an average price of $17.34 per share.

Treasury Stock

During the year ended September 30, 2020, we issued 113,408 shares of common stock from treasury and repurchased 56,806 shares of common stock from our employees to satisfy statutory tax withholding requirements upon the vesting of certain performance phantom stock units under the Equity Incentive Plan. We also repurchased 263,160 shares of common stock on the open market pursuant to our stock repurchase program, and 208,597 shares were forfeited by former employees and returned to treasury stock. During the year ended September 30, 2020, we issued 6,789 unrestricted shares of common stock from treasury to members of our Board of Directors as part of their overall compensation and 5,750 unrestricted shares to satisfy the exercise of outstanding options.

During the year ended September 30, 2019, we issued 216,679 shares of common stock from treasury and repurchased 97,003 shares of common stock from our employees to satisfy statutory tax withholding requirements upon the vesting of certain performance phantom stock units under the Equity Incentive Plan. We also repurchased 467,819 shares of common stock on the open market pursuant to our stock repurchase program. During the year ended September 30, 2019, we issued 1,923 unrestricted shares of common stock from treasury to members of our Board of Directors as part of their overall compensation and 22,500 unrestricted shares to satisfy the exercise of outstanding options. We also issued 283,195 shares out of treasury for restricted shares granted upon the appointment of the Company’s former Chief Executive Officer in March 2019.

Restricted Stock

During the years ended September 30, 2020, 2019, and 2018, we recognized $2,441, $776, and $256, respectively, in compensation expense related to our restricted stock awards. During the year ended September 30, 2020, $1,100 of the compensation expense was settled with cash. At September 30, 2020, the unamortized compensation cost related to outstanding unvested restricted stock was $312. A summary of restricted stock awards for the years ended September 30, 2020, 2019, and 2018 is provided in the table below:


	Year Ended September 30,
	2020	2019	2018
Unvested at beginning of year	283,195	—	140,668
Granted	69,338	283,195	—
Vested	(105,000)	—	(140,668)
Forfeited	(208,597)	—	—
Unvested at end of year	38,936	283,195	—

The fair value of shares vesting during the years ended September 30, 2020, 2019, and 2018 was $2,984, zero and $2,201, respectively. Fair value was calculated as the number of shares vested times the market price of shares on the date of vesting. The weighted average grant date fair value of unvested restricted stock at September 30, 2020 was $23.57.

All the restricted shares granted under the Equity Incentive Plan (vested or unvested) participate in dividends issued to common shareholders, if any.

Director Phantom Stock Units

Director phantom stock units (“Director PSUs”) are primarily granted to the members of the Board of Directors as part of their overall compensation. These Director PSUs are contractual rights to receive one share of the Company's common stock and are paid via unrestricted stock grants to each director upon their departure from the Board of Directors. We record compensation expense for the full value of the grant on the date of grant. For the years ended September 30, 2020, 2019, and 2018, we recognized $390, $300, and $189, respectively, in compensation expense related to these grants.

Employee Phantom Stock Units

An employee phantom stock unit (an “Employee PSU”) is a contractual right to receive one share of the Company’s common stock. Depending on the terms of each grant, Employee PSUs may vest upon the achievement of certain specified performance objectives and continued performance of services, or may vest based on continued performance of services through the vesting date.

As of September 30, 2019, the Company had outstanding Employee PSUs, which, subject to the achievement of certain performance metrics, could have resulted in the issuance of 162,840 shares of common stock. During the year ended September 30, 2020, 3,435

Employee PSUs were forfeited and 45,686 vested, and the Company granted additional Employee PSUs, which, subject to the achievement of certain performance metrics, could result in the issuance of 90,782 shares of common stock. As of September 30, 2020, a maximum of 204,501 shares of common stock may be issued under outstanding Employee PSUs.

During the year ended September 30, 2020 and 2019, we recognized compensation expense of $1,443 and $1,151, respectively, related to Employee PSUs. The vesting of these awards is subject to either the achievement of specified levels of cumulative net income before taxes or specified stock price levels and continued performance of services through mid-December 2021 and 2022, or based on continued performance through the vesting date alone. At September 30, 2020, it is deemed probable that of a portion of the awards which vest based on performance conditions will vest.

Stock Options

We did not issue stock options during the years ended September 30, 2020, 2019 and 2018.

The following table summarizes activity relating to options granted in the years ended September 30, 2013 and 2015.


	Shares	Weighted Average Exercise Price
Outstanding, September 30, 2017	45,750	$	6.42
Options granted	—	—
Exercised	1,500	7.21
Forfeited and canceled	—	—
Outstanding, September 30, 2018	44,250	$	6.39
Options granted	—	—
Exercised	22,500	6.43
Forfeited and canceled	—	—
Outstanding, September 30, 2019	21,750	$	6.35
Options granted	—	—
Exercised	5,750	5.95
Forfeited and canceled	—	—
Outstanding, September 30, 2020	16,000	$	6.49

The following table summarizes options outstanding and exercisable at September 30, 2020:


Outstanding and Exercisable as of September 30, 2020	Remaining Contractual Life in Years	Weighted-Average Exercise Price
8,000	2.58	$5.76
1,000	4.29	$7.27
7,000	4.34	$7.21
16,000		$6.49

Our 2013 and 2015 options cliff vested at the end of a two year period ending at the anniversary date of the grant. All options expire ten years from the grant date if they are not exercised. Upon exercise of stock options, it is our policy to first issue shares from treasury, then issue new shares. Unexercised stock options expire May 2023, January 2025 and February 2025.

During the years ended September 30, 2020, 2019, and 2018, we recognized zero in compensation expense related to our stock option awards.

The intrinsic value of stock options outstanding and exercisable was $405 and $254 at September 30, 2020, and 2019, respectively. The intrinsic value is calculated as the difference between the fair value as of the end of the period and the exercise price of the stock options.

Related Party Transactions (Notes)	12 Months Ended
Related Party Transactions (Notes)	Sep. 30, 2020
Related Party Transactions [Abstract]
Related Party Transactions Disclosure [Text Block]	13. RELATED-PARTY TRANSACTIONS The Company is a party to a sublease agreement with Tontine Associates, for corporate office space in Greenwich, Connecticut. The lease was renewed in November 2019, with monthly rent of approximately $8. Payments by the Company are at a rate consistent with that paid by Tontine Associates to its landlord. See Note 3, “Controlling Shareholder” for additional information regarding Tontine.

Employee Benefit Plans (Notes)	12 Months Ended
Employee Benefit Plans (Notes)	Sep. 30, 2020
Retirement Benefits [Abstract]
Compensation and Employee Benefit Plans [Text Block]	14. EMPLOYEE BENEFIT PLANS 401(k) Plan In November 1998, we established the IES Holdings, Inc. 401(k) Retirement Savings Plan. All full-time IES employees are eligible to participate on the first day of the month subsequent to completing sixty days of service and attaining age twenty-one. Participants become vested in our matching contributions following three years of service. We also maintain several subsidiary retirement savings plans. We recognized $2,326, $2,144, and $1,895 in matching expenses in fiscal years 2020, 2019, and 2018, respectively. Executive Savings Plan Under the Executive Deferred Compensation Plan adopted on July 1, 2004 (the “Executive Savings Plan”), certain employees are permitted to defer a portion (up to 75%) of their base salary and/or bonus for a plan year. The Human Resources and Compensation Committee of the Board of Directors may, in its sole discretion, credit one or more participants with an employer deferral (contribution) in such amount as the Committee may choose (“Employer Contribution”). The Employer Contribution, if any, may be a fixed dollar amount, a fixed percentage of the participant’s compensation, base salary, or bonus, or a “matching” amount with respect to all or part of the participant’s elective deferrals for such plan year, and/or any combination of the foregoing as the Committee may choose. No compensation earned during the years ended September 30, 2020, 2019, or 2018 was deferred under this plan. Post Retirement Benefit Plans Certain individuals at one of the Company’s locations are entitled to receive fixed annual payments that reach a maximum amount, as specified in the related agreements, for a ten year period following retirement or, in some cases, the attainment of 62 years of age. We recognize the unfunded status of the plan in accrued expenses and other non-current liabilities in our Consolidated Balance Sheets. Benefits vest 50% after ten years of service, which increases by 10% per annum until benefits are fully vested after 15 years of service. We had an unfunded benefit liability of $719 and $738 recorded as of September 30, 2020 and 2019, respectively. We recognized compensation expense included in "Selling, general and administrative expenses" in the Consolidated Statement of Comprehensive Income related to these agreements of $41, $42, and zero during the years ended September 30, 2020, 2019, and 2018, respectively. Multiemployer Pension Plan The Infrastructure Solutions segment participates in a multiemployer direct benefit pension plan for employees covered under one of our collective bargaining agreements. We do not administer the plan. We do not significantly participate in this plan. As of December 31, 2019, this plan was funded at 83.32%.

Fair Value Measurements

12 Months Ended

Sep. 30, 2020

Fair Value Disclosures [Abstract]

Fair Value Disclosures [Text Block]

15. FAIR VALUE MEASUREMENTS

Fair value is considered the price to sell an asset, or transfer a liability, between market participants on the measurement date. Fair value measurements assume that (1) the asset or liability is exchanged in an orderly manner, (2) the exchange is in the principal market for that asset or liability, and (3) the market participants are independent, knowledgeable, able and willing to transact an exchange. Fair value accounting and reporting establishes a framework for measuring fair value by creating a hierarchy for observable independent market inputs and unobservable market assumptions and expands disclosures about fair value measurements. Considerable judgment is required to interpret the market data used to develop fair value estimates. As such, the estimates presented herein are not necessarily indicative of the amounts that could be realized in a current exchange. The use of different market assumptions and/or estimation methods could have a material effect on the estimated fair value.

At September 30, 2020, financial assets and liabilities measured at fair value on a recurring basis were limited to our Executive Deferred Compensation Plan, under which certain employees are permitted to defer a portion of their base salary and/or bonus for a Plan Year (as defined in the plan).

Financial assets and liabilities measured at fair value on a recurring basis as of September 30, 2020 and 2019, are summarized in the following tables by the type of inputs applicable to the fair value measurements:


	September 30, 2020
	Total Fair Value		Quoted Prices (Level 1)		Significant Unobservable (Level 3)
Executive savings plan assets	$	766	$	766	$	—
Executive savings plan liabilities	(644)		(644)		—

Total	$	122	$	122	$	—


	September 30, 2019
	Total Fair Value		Quoted Prices (Level 1)		Significant Unobservable (Level 3)
Executive savings plan assets	$	763	$	763	$	—
Executive savings plan liabilities	(646)		(646)		—
Contingent consideration liability	(11)		—		(11)
Total	$	106	$	117	$	(11)

In fiscal years 2016, 2017, and 2018, we entered into contingent consideration arrangements related to certain acquisitions. Please see Note 19, “Business Combinations” for further discussion. At September 30, 2020, we estimated the fair value of these contingent consideration liabilities at zero. The table below presents a reconciliation of the fair value of these obligations, which used significant unobservable inputs (Level 3).


	Contingent Consideration Agreement
Fair Value at September 30, 2019	$	11
Issuances	—
Settlements	—
Net adjustments to fair value	(11)
Fair Value at September 30, 2020	$	—

Below is a description of the inputs used to value the assets summarized in the preceding tables:

Level 1 — Inputs represent unadjusted quoted prices for identical assets exchanged in active markets.

Level 2 — Inputs include directly or indirectly observable inputs other than Level 1 inputs such as quoted prices for similar assets exchanged in active or inactive markets; quoted prices for identical assets exchanged in inactive markets; and other inputs that are considered in fair value determinations of the assets.

Level 3 — Inputs include unobservable inputs used in the measurement of assets. Management is required to use its own assumptions regarding unobservable inputs because there is little, if any, market activity in the assets or related observable inputs that can be corroborated at the measurement date.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Inventory

12 Months Ended

Sep. 30, 2020

Inventory Disclosure [Abstract]

Inventory Disclosure [Text Block]

16. INVENTORY

Inventories consist of the following components:


	September 30,
	2020		2019
Raw materials	$	3,232	$	4,104
Work in process	4,894		6,301
Finished goods	1,186		1,861
Parts and supplies	15,577		9,277
Total inventories	$	24,889	$	21,543

Goodwill and Intangible Assets

12 Months Ended

Sep. 30, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets Disclosure [Text Block]

17. GOODWILL AND INTANGIBLE ASSETS

Goodwill

The following summarizes changes in the carrying value of goodwill by segment for the years ended September 30, 2020 and 2019:


	Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Total
Balance at September 30, 2018	$	2,816	$	9,979	$	30,931	$	6,976	$	50,702
Divestitures	—		—		(119)		—		(119)
Purchase accounting adjustments	—		39		—		—		39
Balance at September 30, 2019	2,816		10,018		30,812		6,976		50,622
Acquisitions (Note 19)	—		6,201		3,916		—		10,117
Goodwill impairment	—		—		—		(6,976)		(6,976)
Balance at September 30, 2020	$	2,816	$	16,219	$	34,728	$	—	$	53,763

Throughout 2020, our Commercial & Industrial reporting unit continued to experience operating losses. Although we have maintained a focus on operational improvements and cost reductions, our performance continued to be affected by the ongoing COVID-19 pandemic and other market factors which delayed the awarding of new projects, decreased demand for new construction in market sectors such as retail, office, and hospitality, and negatively impacted our revenue, profitability and backlog. As a result of this increasingly competitive and uncertain environment, and the financial performance of this reporting unit, we concluded in performing our annual goodwill impairment assessment that the fair value of our Commercial & Industrial reporting unit was less than its carrying amount, which resulted in the recognition of a non-cash goodwill impairment charge of $6,976 for the year ended September 30, 2020.

In performing the goodwill impairment test, we compare each reporting unit’s carrying amount, including goodwill, to the fair value of the reporting unit. The fair value of the reporting unit is estimated using a combination of (i) an analysis of trading multiples of comparable companies (market method) and (ii) discounted projected cash flows (income method). The market method utilizes comparable publicly traded companies’ enterprise values, as compared to their recent and forecasted earnings. The income method measures the present value of the reporting unit’s projected future annual cash flows over the next five years with a terminal value assumption. We use a variety of underlying assumptions to estimate these future cash flows, including assumptions relating to future economic market conditions, costs and expenses and capital expenditures.

We believe the combination of these approaches and our judgment regarding underlying assumptions and estimates provides us with the best estimate of fair value for each of our reporting units, and that these valuation methods are widely used by market participants in our industry. The fair value of our reporting units is affected by assumptions regarding future market conditions and the demand for our services, our ability to execute future projects successfully, and the cost of capital. Our estimate of fair value requires us to use significant unobservable inputs, representative of Level 3 fair value measurements.

Intangible Assets

Intangible assets consist of the following:


				September 30, 2020
	Estimated Useful Lives (in Years)			Gross Carrying Amount		Accumulated Amortization		Net
Trademarks/trade names	5	-	20	$	7,754	$	(1,741)	$	6,013
Technical library	20			400		(141)		259
Customer relationships	6	-	15	46,449		(14,900)		31,549
Non-competition arrangements	5			40		(17)		23
Backlog and construction contracts	1			3,383		(1,870)		1,513
Total				$	58,026	$	(18,669)	$	39,357


				September 30, 2019
	Estimated Useful Lives (in Years)			Gross Carrying Amount		Accumulated Amortization		Net
Trademarks/trade names	5	-	20	$	5,084	$	(1,267)	$	3,817
Technical library	20			400		(121)		279
Customer relationships	6	-	15	33,539		(11,051)		22,488
Non-competition arrangements	5			40		(9)		31
Backlog and construction contracts	1			599		(591)		8
Total				$	39,662	$	(13,039)	$	26,623

For the years ended September 30, 2020, 2019, and 2018, amortization expense of intangible assets was $6,424, $3,950 and $4,101, respectively. Our estimated future amortization expense for years ending September 30 is as follows:


Year Ending September 30,
2021	$	6,217
2022	4,634
2023	4,241
2024	3,898
2025	3,571
Thereafter	16,796
Total	$	39,357

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure [Text Block]	18. COMMITMENTS AND CONTINGENCIES Legal Matters From time to time we are a party to various claims, lawsuits and other legal proceedings that arise in the ordinary course of business. We maintain various insurance coverages to minimize financial risk associated with these proceedings. None of these proceedings, separately or in the aggregate, are expected to have a material adverse effect on our financial position, results of operations or cash flows. With respect to all such proceedings, we record reserves when it is probable that a liability has been incurred and the amount of loss can be reasonably estimated. We expense routine legal costs related to these proceedings as they are incurred. As of September 30, 2020, we did not have any material pending legal proceedings. Risk Management We retain the risk for workers’ compensation, employer’s liability, automobile liability, construction defects, general liability and employee group health claims, as well as pollution coverage, resulting from uninsured deductibles per accident or occurrence which are generally subject to annual aggregate limits. Our general liability program provides coverage for bodily injury and property damage. In many cases, we insure third parties, including general contractors, as additional insureds under our insurance policies. Losses are accrued based upon our known claims incurred and an estimate of claims incurred but not reported. As a result, many of our claims are effectively self-insured. Many claims against our insurance are in the form of litigation. At September 30, 2020 and 2019, we had $6,254 and $6,683, respectively, accrued for self-insurance liabilities. We are also subject to construction defect liabilities, primarily within our Residential segment. As of September 30, 2020 and 2019, we had $36 and $90, respectively, reserved for these claims. Because the reserves are based on judgment and estimates, and involve variables that are inherently uncertain, such as the outcome of litigation and an assessment of insurance coverage, there can be no assurance that the ultimate liability will not be higher or lower than such estimates or that the timing of payments will not create liquidity issues for the Company. Some of the underwriters of our casualty insurance program require us to post letters of credit as collateral. This is common in the insurance industry. To date, we have not had a situation where an underwriter has had reasonable cause to effect payment under a letter of credit. At September 30, 2020, $5,464 of our outstanding letters of credit was utilized to collateralize our insurance program. Surety As of September 30, 2020, the estimated cost to complete our bonded projects was approximately $92,856. We evaluate our bonding requirements on a regular basis, including the terms offered by our sureties. We believe the bonding capacity presently provided by our current sureties is adequate for our current operations and will be adequate for our operations for the foreseeable future. Posting letters of credit in favor of our sureties reduces the borrowing availability under our revolving credit facility. Other Commitments and Contingencies Some of our customers and vendors require us to post letters of credit, or provide intercompany guarantees, as a means of guaranteeing performance under our contracts and ensuring payment by us to subcontractors and vendors. If our customer has reasonable cause to effect payment under a letter of credit, we would be required to reimburse our creditor for the letter of credit. At September 30, 2020, $200 of our outstanding letters of credit were to collateralize our vendors. From time to time, we may enter into firm purchase commitments for materials, such as copper or aluminum wire, which we expect to use in the ordinary course of business. These commitments are typically for terms of less than one year and require us to buy minimum quantities of materials at specific intervals at a fixed price over the term. As of September 30, 2020, we had no such significant commitments.

Business Combinations and Divestitures

12 Months Ended

Sep. 30, 2020

Business Combinations [Abstract]

Business Combination Disclosure [Text Block]

19. BUSINESS COMBINATIONS

The Company completed two acquisitions during the year ended September 30, 2020 for a total aggregate cash consideration of $28,952.

• Aerial Lighting & Electric, Inc. (“Aerial”) – On February 18, 2020, we acquired 100% of the equity interests in Aerial, a Naugatuck, Connecticut-based electrical contractor specializing in the design and installation of electrical systems for multi-family developments. The acquisition of Aerial furthers our Residential segment's growth strategy by providing a foothold in the Northeast market.

• Plant Power & Control Systems, LLC (“PPCS”) – On February 21, 2020, we acquired 100% of the membership interests in PPCS, a Birmingham, Alabama-based manufacturer and installer of custom engineered power distribution equipment. The acquisition of PPCS furthers our Infrastructure Solutions segment's growth strategy by accelerating their expansion in the Southeast market.

The Company accounted for the transactions under the acquisition method of accounting, which requires recording assets and liabilities at fair value (Level 3). The valuation of the assets and liabilities assumed is as follows:


Current assets	$	5,660
Property and equipment	489
Operating right of use asset	331
Intangible assets	18,276
Goodwill	10,117
Current liabilities	(3,802)
Operating long-term lease liabilities	(170)
Deferred tax liability	(1,949)
Net assets acquired	$	28,952

With regard to goodwill, the balance is attributable to the workforce of the acquired business and other intangibles that do not qualify for separate recognition. In connection with these acquisitions, we acquired goodwill of $10,117 of which $3,916 is tax deductible.

The intangible assets acquired primarily consisted of customer relationships with a total weighted-average amortization period of 8.8 years.

In conjunction with these acquisitions, we acquired receivables totaling $3,190, of which we estimated none to be uncollectible at the date of acquisition. These acquisitions contributed $21,836 in revenue and $812 in operating income during the year ended September 30, 2020.

Unaudited Pro Forma Information

The following unaudited supplemental pro forma results of operations for the year ended September 30, 2020 are calculated as if each acquisition occurred as of October 1 of the fiscal year prior to consummation.


		Unaudited
		Twelve Months Ended September 30,
		2020		2019
Revenues	$	1,208,020	$	1,118,460
Net income attributable to IES Holdings, Inc.	$	43,285	$	34,967

Subsequent Events	12 Months Ended
Subsequent Events	Sep. 30, 2020
Subsequent Events [Abstract]
Subsequent Events	20. SUBSEQUENT EVENTS On November 5, 2020, we acquired all of the stock in K.E.P. Electric, Inc., a Batavia, Ohio-based electrical contractor specializing in the design and installation of electrical systems for single-family housing and multi-family developments. This business will operate as a subsidiary in our Residential segment. On November 19, 2020, we acquired all of the stock of Wedlake Fabricating, Inc., a Tulsa, Oklahoma-based manufacturer of custom generator enclosures. This business will operate as a subsidiary in our Infrastructure Solutions segment. The acquisitions were financed using cash on hand, and do not have a material impact on our overall liquidity.

Quarterly Results of Operations (Notes)

12 Months Ended

Sep. 30, 2020

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Information [Text Block]

21. QUARTERLY RESULTS OF OPERATIONS (UNAUDITED)

Quarterly financial information for the years ended September 30, 2020 and 2019 is summarized as follows:


	Year Ended September 30, 2020
	First		Second		Third		Fourth
	Quarter		Quarter		Quarter		Quarter
Revenues	$	276,043	$	291,277	$	293,125	$	330,411
Gross profit	$	50,215	$	51,264	$	58,320	$	68,160
Net income (loss) attributable to IES Holdings, Inc.	$	8,502	$	6,231	$	12,260	$	14,606

Earnings (loss) per share attributable to IES Holdings, Inc.:
Basic	$	0.40	$	0.30	$	0.58	$	0.69
Diluted	$	0.39	$	0.29	$	0.58	$	0.68


	Year Ended September 30, 2019
	First		Second		Third		Fourth
	Quarter		Quarter		Quarter		Quarter
Revenues	$	243,842	$	256,914	$	282,633	$	293,607
Gross profit	$	41,601	$	43,235	$	46,397	$	50,870
Net income (loss) attributable to IES Holdings, Inc.	$	6,884	$	5,489	$	10,972	$	9,861

Earnings (loss) per share attributable to IES Holdings, Inc.:
Basic	$	0.32	$	0.26	$	0.52	$	0.47
Diluted	$	0.32	$	0.26	$	0.52	$	0.46

The sum of the individual quarterly earnings per share amounts may not agree with year-to-date earnings per share as each period’s computation is based on the weighted average number of shares outstanding during the period.

We recorded a goodwill impairment charge of $6,976 in the fourth quarter 2020.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Sep. 30, 2020

Accounting Policies [Abstract]

Significant Accounting Policies [Text Block]

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Principles of Consolidation

Asset Impairment

Use of Estimates

Cash and Cash Equivalents

We consider all highly liquid investments purchased with an original maturity of three months or less to be cash equivalents.

Inventories

Property and Equipment

Goodwill

Intangible Assets

Intangible assets with definite lives are amortized over their estimated useful lives based on expected economic benefit with no residual value.

Debt Issuance Costs

Revenue Recognition

Accounts Receivable and Allowance for Doubtful Accounts

Comprehensive Income (Loss)

Comprehensive income (loss) includes all changes in equity during a period except those resulting from investments by and distributions to stockholders.

Income Taxes

Risk Management


Year Ended September 30:
	2021	$	1,195
	2022		839
	2023		538
	2024		347
	2025		217
	Thereafter		750
Total		$	3,886

We had letters of credit totaling $5,464 outstanding at September 30, 2020 to collateralize certain of our high deductible insurance obligations.

Realization of Long-Lived Assets

Risk Concentration

No single customer accounted for more than 10% of our consolidated revenues for the years ended September 30, 2020, 2019 and 2018.

Fair Value of Financial Instruments

Stock-Based Compensation

Deferred Compensation Plans

Noncontrolling Interest

Leases

Accounting Standards Not Yet Adopted

Accounting Standards Recently Adopted

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Sep. 30, 2020

Accounting Policies [Abstract]

Periods of Expected Insurance Payments

Based on historical payment patterns, we expect payments of undiscounted ultimate losses to be made as follows:


Year Ended September 30:
	2021	$	1,195
	2022		839
	2023		538
	2024		347
	2025		217
	Thereafter		750
Total		$	3,886

Revenue Recognition (Tables)

12 Months Ended

Sep. 30, 2020

Revenue Recognition and Deferred Revenue [Abstract]

Disaggregation of Revenue [Table Text Block]


	Year Ended September 30,
	2020		2019		2018
Communications	$	395,141	$	321,246	$	219,655
Residential
Single-family	239,140		212,358		190,379
Multi-family and Other	172,650		100,978		95,332
Total Residential	411,790		313,336		285,711
Infrastructure Solutions
Industrial Services	40,701		48,948		44,701
Custom Power Solutions	87,678		87,842		52,462
Total Infrastructure Solutions	128,379		136,790		97,163
Commercial & Industrial	255,546		305,624		274,299
Total Revenue	$	1,190,856	$	1,076,996	$	876,828


	Year Ended September 30, 2020
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Total
Fixed-price		$	309,567	$	411,790	$	121,922	$	241,864	$	1,085,143
Time-and-material		85,574		—		6,457		13,682		105,713
Total revenue		$	395,141	$	411,790	$	128,379	$	255,546	$	1,190,856


	Year Ended September 30, 2019
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Total
Fixed-price		$	229,143	$	313,336	$	129,096	$	286,319	$	957,894
Time-and-material		92,103		—		7,694		19,305		119,102
Total revenue		$	321,246	$	313,336	$	136,790	$	305,624	$	1,076,996

	Year Ended September 30, 2018
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Total
Fixed-price		$	166,258	$	285,711	$	90,155	$	244,464	$	786,588
Time-and-material		53,397		—		7,008		29,835		90,240
Total revenue		$	219,655	$	285,711	$	97,163	$	274,299	$	876,828

Property and Equipment (Tables)

12 Months Ended

Sep. 30, 2020

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment [Table Text Block]


	Estimated Useful Lives in Years			Year Ended September 30,
				2020		2019
Land	N/A			$	1,436	$	1,436
Buildings and improvements	5	-	20	14,378		13,608
Machinery and equipment	3	-	10	32,695		30,600
Information systems	2	-	8	8,496		7,945
Furniture and fixtures	5	-	7	1,746		1,587
				$	58,751	$	55,176
Less-Accumulated depreciation				(34,544)		(29,560)
Construction in progress				382		130
Property and equipment, net				$	24,589	$	25,746

Per Share Information (Tables)

12 Months Ended

Sep. 30, 2020

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]


	Year Ended September 30,
	2020		2019		2018
Numerator:
Net income (loss) attributable to common shareholders of IES Holdings, Inc.	$	40,830	$	32,950	$	(14,113)
Increase (decrease) in noncontrolling interest	194		—		(44)
Net income attributable to restricted shareholders of IES Holdings, Inc.	575		256		—
Net income (loss) attributable to IES Holdings, Inc.	$	41,599	$	33,206	$	(14,157)

Denominator:
Weighted average common shares outstanding — basic	20,795,892		21,082,012		21,196,388
Effect of dilutive stock options and non-vested securities	296,518		233,233		—
Weighted average common and common equivalent shares outstanding — diluted	21,092,410		21,315,245		21,196,388

Earnings (loss) per share attributable to common shareholders of IES Holdings, Inc.:
Basic	$	1.96	$	1.56	$	(0.67)
Diluted	$	1.94	$	1.55	$	(0.67)

Detail of Certain Balance Sheet Accounts (Tables)

12 Months Ended

Sep. 30, 2020

Detail of Certain Balance Sheet Accounts [Abstract]

Accounts Receivable, Allowance for Credit Loss [Table Text Block]


	Year Ended September 30,
	2020		2019
Balance at beginning of period	$	1,184	$	868
Additions to costs and expenses	1,864		552
Deductions for uncollectible receivables written off, net of recoveries	(435)		(236)
Balance at end of period	$	2,613	$	1,184

Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]


	Year Ended September 30,
	2020		2019
Accounts payable, trade	$	93,315	$	85,276
Accrued compensation and benefits	53,933		42,828
Accrued insurance liabilities	6,254		6,683
Current operating lease liabilities	11,056		—
Other accrued expenses	22,152		18,122
	$	186,710	$	152,909

Schedule of Other Assets [Table Text Block]


	Year Ended September 30,
	2020		2019
Executive Savings Plan assets	$	766	$	763
Securities and equity investments	—		408
Other	5,014		3,767
Total	$	5,780	$	4,938

Debt (Tables)

12 Months Ended

Sep. 30, 2020

Debt Disclosure [Abstract]

Schedule of Debt [Table Text Block]


	Year Ended September 30,
	2020		2019
Revolving loan (long-term debt)	$	12	$	—
Debt issuance costs (1)	—		—
Other long-term debt	205		299
Total debt	$	217	$	299

Leases (Tables)

12 Months Ended

Sep. 30, 2020

Leases [Abstract]

Lessee, Operating Lease, Liability, Maturity

The maturities of our lease liabilities as of September 30, 2020, are as follows:


	Operating Leases		Finance Leases		Total
2021	$	11,269	$	430	$	11,699
2022	8,743		403		9,146
2023	5,822		401		6,223
2024	3,488		368		3,856
2025	2,110		167		2,277
Thereafter	3,175		—		3,175
Total undiscounted lease payments	$	34,607	$	1,769	$	36,376
Less: imputed interest	3,021		182		3,203
Present value of lease liabilities	$	31,586	$	1,587	$	33,173

Lease, Cost

Lease cost recognized in our Consolidated Statements of Comprehensive Income is summarized as follows:


	Year Ended
	September 30, 2020
Operating lease cost	$	12,910
Finance lease cost
Amortization of lease assets	203
Interest on lease liabilities	47
Finance lease cost	250
Short-term lease cost	1,163
Variable lease cost	827
Total lease cost	$	15,150

Schedule of Cash Flow, Supplemental Disclosures

Other information about lease amounts recognized in our Consolidated Financial Statements is summarized as follows:


	Year Ended
	September 30, 2020
Operating cash flows used for operating leases	$	12,934
Operating cash flows used for finance leases	47
Right-of-use assets obtained in exchange for new operating lease liabilities	10,640
Right-of-use assets obtained in exchange for new finance lease liabilities	1,803


	September 30, 2020
Weighted-average remaining lease term - operating leases	4.3 years
Weighted-average remaining lease term - finance leases	4.4 years
Weighted-average discount rate - operating leases	3.9	%
Weighted-average discount rate - finance leases	5.1	%

Income Taxes (Tables)

12 Months Ended

Sep. 30, 2020

Income Tax Disclosure [Abstract]

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]


	Year Ended September 30,
	2020		2019		2018
Federal:
Current	$	(39)	$	(1,330)	$	(2,345)
Deferred	9,317		5,908		38,744
State:
Current	3,657		2,312		1,536
Deferred	(4,195)		(227)		216
Total provision for income taxes	$	8,740	$	6,663	$	38,151

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]


	Year Ended September 30,
	2020		2019		2018
Provision at the statutory rate (1)	$	10,352	$	8,430	$	5,973
Increase resulting from:
Non-deductible expenses	1,974		1,277		1,241
State income taxes, net of federal deduction	2,662		2,009		1,193
Change in valuation allowance	—		—		1,761
Rate change	—		—		31,333
Other	261		—		183
Decrease resulting from:
Share-based compensation	(75)		(556)		(238)
Change in valuation allowance	(3,334)		(83)		—
Contingent tax liabilities	(1,313)		(3,967)		(1,908)
Component 2 goodwill utilization	(1,787)		(144)		—
State deferred true up	—		—		(1,387)
Other	—		(303)		—
Total provision for income taxes	$	8,740	$	6,663	$	38,151

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]


	Year Ended September 30,
	2020		2019
Deferred income tax assets:
Allowance for doubtful accounts	$	592	$	245
Accrued expenses	14,619		9,783
Net operating loss carryforward	22,623		39,045
Various reserves	1,764		1,396
Equity losses in affiliate	210		119
Share-based compensation	897		672
Capital loss carryforward	74		74
Lease asset	7,681		—
Other	2,444		1,137
Subtotal	50,904		52,471
Less valuation allowance	710		4,044
Total deferred income tax assets	50,194		48,427
Deferred income tax liabilities:
Property and equipment	517		840
Intangible assets	7,926		5,978
Lease liability	7,677		—
Other	271		735
Total deferred income tax liabilities	16,391		7,553
Net deferred income tax assets	$	33,803	$	40,874

Summary of Income Tax Contingencies [Table Text Block]


	Year Ended September 30,
	2020		2019
Balance at beginning of period	$	26,294	$	30,256
Additions for position related to current year	111		93
Additions for positions of prior years	29		19
Reduction resulting from the lapse of the applicable statutes of limitations	1,573		4,074


Balance at end of period	$	24,861	$	26,294

Operating Segments (Tables)

12 Months Ended

Sep. 30, 2020

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]


		Year Ended September 30, 2020
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Corporate		Total
Revenues		$	395,141	$	411,790	$	128,379	$	255,546	$	—	$	1,190,856
Cost of services		317,013		318,034		93,358		234,492		—		962,897
Gross profit		78,128		93,756		35,021		21,054		—		227,959
Selling, general and administrative		37,674		63,668		20,418		32,128		17,023		170,911
Goodwill impairment expense		—		—		—		6,976		—		6,976
Contingent consideration		—		—		—		(11)		—		(11)
Loss (gain) on sale of assets		8		2		35		(45)		—		—
Income (loss) from operations		$	40,446	$	30,086	$	14,568	$	(17,994)	$	(17,023)	$	50,083
Other data:
	Depreciation and amortization expense	$	1,351	$	2,276	$	6,020	$	2,768	$	93	$	12,508
	Capital expenditures	$	830	$	1,459	$	795	$	1,362	$	299	$	4,745
	Total assets	$	154,808	$	110,998	$	124,640	$	68,318	$	101,764	$	560,528


		Year Ended September 30, 2019
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Corporate		Total
Revenues		$	321,246	$	313,336	$	136,790	$	305,624	$	—	$	1,076,996
Cost of services		264,746		248,562		105,863		275,722		—		894,893
Gross profit		56,500		64,774		30,927		29,902		—		182,103
Selling, general and administrative		31,850		46,864		18,664		27,815		15,382		140,575
Contingent consideration		(97)		—		(277)		—		—		(374)
Loss (gain) on sale of assets		(6)		(17)		105		(30)		—		52
Income (loss) from operations		$	24,753	$	17,927	$	12,435	$	2,117	$	(15,382)	$	41,850
Other data:
	Depreciation and amortization expense	$	1,513	$	852	$	4,528	$	2,563	$	101	$	9,557
	Capital expenditures	$	973	$	1,412	$	1,377	$	2,402	$	136	$	6,300
	Total assets	$	109,263	$	63,903	$	116,867	$	82,050	$	73,175	$	445,258


		Year Ended September 30, 2018
		Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Corporate		Total
Revenues		$	219,655	$	285,711	$	97,163	$	274,299	$	—	$	876,828
Cost of services		179,518		227,355		75,337		244,656		—		726,866
Gross profit		40,137		58,356		21,826		29,643		—		149,962
Selling, general and administrative		26,003		41,401		18,293		27,031		11,192		123,920
Contingent consideration		(85)		—		288		(100)		—		103
Loss (gain) on sale of assets		(4)		8		18		(37)		—		(15)
Income (loss) from operations		$	14,223	$	16,947	$	3,227	$	2,749	$	(11,192)	$	25,954
Other data:
	Depreciation and amortization expense	$	1,247	$	637	$	4,672	$	2,197	$	107	$	8,860
	Capital expenditures	$	647	$	932	$	735	$	2,216	$	33	$	4,563
	Total assets	$	80,528	$	55,176	$	109,506	$	89,729	$	87,055	$	421,994

Stockholders' Equity (Tables)

12 Months Ended

Sep. 30, 2020

Equity [Abstract]

Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]


	Year Ended September 30,
	2020	2019	2018
Unvested at beginning of year	283,195	—	140,668
Granted	69,338	283,195	—
Vested	(105,000)	—	(140,668)
Forfeited	(208,597)	—	—
Unvested at end of year	38,936	283,195	—

Share-based Payment Arrangement, Option, Activity [Table Text Block]


	Shares	Weighted Average Exercise Price
Outstanding, September 30, 2017	45,750	$	6.42
Options granted	—	—
Exercised	1,500	7.21
Forfeited and canceled	—	—
Outstanding, September 30, 2018	44,250	$	6.39
Options granted	—	—
Exercised	22,500	6.43
Forfeited and canceled	—	—
Outstanding, September 30, 2019	21,750	$	6.35
Options granted	—	—
Exercised	5,750	5.95
Forfeited and canceled	—	—
Outstanding, September 30, 2020	16,000	$	6.49

Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding and Exercisable [Table Text Block]


Outstanding and Exercisable as of September 30, 2020	Remaining Contractual Life in Years	Weighted-Average Exercise Price
8,000	2.58	$5.76
1,000	4.29	$7.27
7,000	4.34	$7.21
16,000		$6.49

Fair Value Measurements (Tables)

12 Months Ended

Sep. 30, 2020

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]


	September 30, 2020
	Total Fair Value		Quoted Prices (Level 1)		Significant Unobservable (Level 3)
Executive savings plan assets	$	766	$	766	$	—
Executive savings plan liabilities	(644)		(644)		—

Total	$	122	$	122	$	—


	September 30, 2019
	Total Fair Value		Quoted Prices (Level 1)		Significant Unobservable (Level 3)
Executive savings plan assets	$	763	$	763	$	—
Executive savings plan liabilities	(646)		(646)		—
Contingent consideration liability	(11)		—		(11)
Total	$	106	$	117	$	(11)

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]


	Contingent Consideration Agreement
Fair Value at September 30, 2019	$	11
Issuances	—
Settlements	—
Net adjustments to fair value	(11)
Fair Value at September 30, 2020	$	—

Inventory (Tables)

12 Months Ended

Sep. 30, 2020

Inventory Disclosure [Abstract]

Schedule of Inventory, Current [Table Text Block]


	September 30,
	2020		2019
Raw materials	$	3,232	$	4,104
Work in process	4,894		6,301
Finished goods	1,186		1,861
Parts and supplies	15,577		9,277
Total inventories	$	24,889	$	21,543

Goodwill and Intangible Assets (Tables)

12 Months Ended

Sep. 30, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill [Table Text Block]


	Communications		Residential		Infrastructure Solutions		Commercial & Industrial		Total
Balance at September 30, 2018	$	2,816	$	9,979	$	30,931	$	6,976	$	50,702
Divestitures	—		—		(119)		—		(119)
Purchase accounting adjustments	—		39		—		—		39
Balance at September 30, 2019	2,816		10,018		30,812		6,976		50,622
Acquisitions (Note 19)	—		6,201		3,916		—		10,117
Goodwill impairment	—		—		—		(6,976)		(6,976)
Balance at September 30, 2020	$	2,816	$	16,219	$	34,728	$	—	$	53,763

Schedule of Finite-Lived Intangible Assets [Table Text Block]


				September 30, 2019
	Estimated Useful Lives (in Years)			Gross Carrying Amount		Accumulated Amortization		Net
Trademarks/trade names	5	-	20	$	5,084	$	(1,267)	$	3,817
Technical library	20			400		(121)		279
Customer relationships	6	-	15	33,539		(11,051)		22,488
Non-competition arrangements	5			40		(9)		31
Backlog and construction contracts	1			599		(591)		8
Total				$	39,662	$	(13,039)	$	26,623

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]


Year Ending September 30,
2021	$	6,217
2022	4,634
2023	4,241
2024	3,898
2025	3,571
Thereafter	16,796
Total	$	39,357

Business Combinations and Divestitures (Tables)

12 Months Ended

Sep. 30, 2020

Business Combinations [Abstract]

Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]


Current assets	$	5,660
Property and equipment	489
Operating right of use asset	331
Intangible assets	18,276
Goodwill	10,117
Current liabilities	(3,802)
Operating long-term lease liabilities	(170)
Deferred tax liability	(1,949)
Net assets acquired	$	28,952

Business Acquisition, Pro Forma Information


		Unaudited
		Twelve Months Ended September 30,
		2020		2019
Revenues	$	1,208,020	$	1,118,460
Net income attributable to IES Holdings, Inc.	$	43,285	$	34,967

Quarterly Results of Operations (Tables)

12 Months Ended

Sep. 30, 2020

Quarterly Financial Information Disclosure [Abstract]

Quarterly Financial Information [Table Text Block]

Quarterly financial information for the years ended September 30, 2020 and 2019 is summarized as follows:


	Year Ended September 30, 2020
	First		Second		Third		Fourth
	Quarter		Quarter		Quarter		Quarter
Revenues	$	276,043	$	291,277	$	293,125	$	330,411
Gross profit	$	50,215	$	51,264	$	58,320	$	68,160
Net income (loss) attributable to IES Holdings, Inc.	$	8,502	$	6,231	$	12,260	$	14,606

Earnings (loss) per share attributable to IES Holdings, Inc.:
Basic	$	0.40	$	0.30	$	0.58	$	0.69
Diluted	$	0.39	$	0.29	$	0.58	$	0.68


	Year Ended September 30, 2019
	First		Second		Third		Fourth
	Quarter		Quarter		Quarter		Quarter
Revenues	$	243,842	$	256,914	$	282,633	$	293,607
Gross profit	$	41,601	$	43,235	$	46,397	$	50,870
Net income (loss) attributable to IES Holdings, Inc.	$	6,884	$	5,489	$	10,972	$	9,861

Earnings (loss) per share attributable to IES Holdings, Inc.:
Basic	$	0.32	$	0.26	$	0.52	$	0.47
Diluted	$	0.32	$	0.26	$	0.52	$	0.46

Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Oct. 01, 2019
Accounting Policies [Abstract]
Goodwill impairment expense	$ 6,976	$ 6,976	$ 0	$ 0
Deferred financing cost amortization		152	318	288
Debt Issuance Costs, Noncurrent, Net	736	736	782
Accounts Receivable, Allowance for Credit Loss	(2,613)	(2,613)	(1,184)	(868)
Deferred tax assets	$ 33,803	33,803	40,874
Loss Contingency, Undiscounted Amount of Insurance-related Assessment Liability		3,886	$ 4,975
Accrual for Loss Contingencies, Undiscounted, First Year		1,195
Accrual for Loss Contingencies, Undiscounted, Second Year		839
Accrual for Loss Contingencies, Undiscounted, Third Year		538
Accrual for Loss Contingencies, Undiscounted, Fourth Year		347
Accrual for Loss Contingencies, Undiscounted, Fifth Year		217
Accrual for Insurance Loss Contingencies, Undiscounted, after Fifth Year		$ 750
Loss Contingency Accrual, Insurance-related Assessment, Discount Rate	0.30%	0.30%	1.60%
Accrued Insurance, Current	$ 3,832	$ 3,832	$ 4,702
Liability for Claims and Claims Adjustment Expense, Disability, Accident and Health	2,422	2,422	1,981
Letters of Credit Outstanding, Amount	5,664	5,664
Redeemable Noncontrolling Interest, Equity, Redemption Value	1,582	1,582
Noncontrolling Interest, Change in Redemption Value		(194)		$ 44
Operating right of use assets	31,786	31,786	$ 0		$ 32,434
Operating Lease, Liability	$ 31,586	$ 31,586			$ 32,237

Controlling Shareholder (Details) $ in Thousands	12 Months Ended
Controlling Shareholder (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Risks and Uncertainties [Abstract]
ControllingShareholderOwnershipPercentage	56.00%
Related Party Transaction, Purchases from Related Party	$ 8

Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
Revenue Recognition (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Revenue Recognition and Deferred Revenue [Abstract]
Capitalized Contract Cost, Net	$ 94								$ 94
Disaggregation of Revenue [Line Items]
Revenues	330,411	$ 293,125	$ 291,277	$ 276,043	$ 293,607	$ 282,633	$ 256,914	$ 243,842	1,190,856	$ 1,076,996	$ 876,828
Unbilled Receivables, Current	10,710								10,710
Contract with Customer, Liability, Revenue Recognized									34,035	31,831
Revenue, Remaining Performance Obligation, Amount	505,352								505,352
Performance Obligation Next 12 Months	$ 438,253								438,253
Communications [Member]
Disaggregation of Revenue [Line Items]
Revenues									395,141	321,246	219,655
Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues									411,790	313,336	285,711
Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues									128,379	136,790	97,163
Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues									255,546	305,624	274,299
Fixed-price Contract [Member]
Disaggregation of Revenue [Line Items]
Revenues									1,085,143	957,894	786,588
Fixed-price Contract [Member] \| Communications [Member]
Disaggregation of Revenue [Line Items]
Revenues									309,567	229,143	166,258
Fixed-price Contract [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues									411,790	313,336	285,711
Fixed-price Contract [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues									121,922	129,096	90,155
Fixed-price Contract [Member] \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues									241,864	286,319	244,464
Time-and-materials Contract [Member]
Disaggregation of Revenue [Line Items]
Revenues									105,713	119,102	90,240
Time-and-materials Contract [Member] \| Communications [Member]
Disaggregation of Revenue [Line Items]
Revenues									85,574	92,103	53,397
Time-and-materials Contract [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues									0	0	0
Time-and-materials Contract [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues									6,457	7,694	7,008
Time-and-materials Contract [Member] \| Commercial and Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues									13,682	19,305	29,835
industrial Services [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues									40,701	48,948	44,701
Custom Power Solutions [Member] \| Infrastructure Solutions [Member]
Disaggregation of Revenue [Line Items]
Revenues									87,678	87,842	52,462
Single Family Contracts [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues									239,140	212,358	190,379
Multi Family and Other [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues									$ 172,650	$ 100,978	$ 95,332

Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Property, Plant and Equipment [Line Items]
Land	$ 1,436	$ 1,436
Buildings and Improvements, Gross	14,378	13,608
Machinery and Equipment, Gross	32,695	30,600
Capitalized Computer Software, Gross	8,496	7,945
Furniture and Fixtures, Gross	1,746	1,587
Property, Plant and Equipment, Gross	58,751	55,176
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(34,544)	(29,560)
Construction in Progress, Gross	382	130
Property and equipment, net	24,589	25,746
Depreciation	$ 6,084	$ 5,607	$ 4,759
Building and Building Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years	5 years
Building and Building Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	20 years	20 years
Machinery and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years	3 years
Machinery and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	10 years	10 years
Software and Software Development Costs [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	2 years	2 years
Software and Software Development Costs [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	8 years	8 years
Furniture and Fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years	5 years
Furniture and Fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	7 years	7 years

Per Share Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Undistributed Earnings (Loss) Available to Common Shareholders, Basic									$ 40,830	$ 32,950	$ (14,113)
Noncontrolling Interest, Period Increase (Decrease)									194	0	(44)
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic									575	256	0
Comprehensive income (loss) attributable to IES Holdings, Inc.	$ 14,606	$ 12,260	$ 6,231	$ 8,502	$ 9,861	$ 10,972	$ 5,489	$ 6,884	$ 41,599	$ 33,206	$ (14,157)
Weighted Average Number of Shares Outstanding, Basic									20,795,892	21,082,012	21,196,388
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements									296,518	233,233	0
Weighted Average Number of Shares Outstanding, Diluted									21,092,410	21,315,245	21,196,388
Earnings (loss) per share, basic	$ 0.69	$ 0.58	$ 0.30	$ 0.40	$ 0.47	$ 0.52	$ 0.26	$ 0.32	$ 1.96	$ 1.56	$ (0.67)
Earnings (loss) per share, diluted	$ 0.68	$ 0.58	$ 0.29	$ 0.39	$ 0.46	$ 0.52	$ 0.26	$ 0.32	$ 1.94	$ 1.55	$ (0.67)
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount											301,879

Detail of Certain Balance Sheet Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Detail of Certain Balance Sheet Accounts [Abstract]
Accounts Receivable, Allowance for Credit Loss, Beginning	$ 1,184	$ 868
Addition to costs and expenses	1,864	552
Deductions for uncollectible receivables written off, net of recoveries	(435)	(236)
Accounts Receivable, Allowance for Credit Loss, Ending	2,613	1,184
Accounts payable, trade	93,315	85,276
Accrued compensation and benefits	53,933	42,828
Accrued insurance liabilities	6,254	6,683
Current operating lease liabilities	11,056
Other accrued expenses	22,152	18,122
Accounts payable and accrued expenses	186,710	152,909
Executive Savings Plan assets	766	763
Securities and equity investments	0	408
Other	5,014	3,767
Other non-current assets	$ 5,780	$ 4,938

Debt (Details) $ in Thousands	12 Months Ended
Debt (Details) $ in Thousands	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)
Debt Disclosure [Abstract]
Revolving loan	$ 12	$ 0
Other long-term debt	205	299
Long-term debt	217	299
Debt Issuance Costs, Noncurrent, Net	736	$ 782
Letters of Credit Outstanding, Amount	5,664
Line of Credit Facility, Remaining Borrowing Capacity	94,324
Line of Credit Facility, Interest Rate at Period End		1.48%
Interest expense	777	$ 1,857	$ 1,946
Line of Credit Facility, Maximum Borrowing Capacity	100,000
Liquidity	$ 147,902
Fixed Charge Coverage Ratio	8.3

Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Oct. 01, 2019
Leases [Abstract]
Current operating lease liabilities	$ 11,056
Current finance lease liabilities	418
Lessee, Operating Lease, Liability, Payments, Due Year One	11,269
Lessee, Operating Lease, Liability, Payments, Due Year Two	8,743
Lessee, Operating Lease, Liability, Payments, Due Year Three	5,822
Lessee, Operating Lease, Liability, Payments, Due Year Four	3,488
Lessee, Operating Lease, Liability, Payments, Due Year Five	2,110
Lessee, Operating Lease, Liability, Payments, Due after Year Five	3,175
Lessee, Operating Lease, Liability, Payments, Due	34,607
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	3,021
Operating Lease, Liability	31,586			$ 32,237
Finance Lease, Liability, Payments, Due Year One	430
Finance Lease, Liability, Payments, Due Year Two	403
Finance Lease, Liability, Payments, Due Year Three	401
Finance Lease, Liability, Payments, Due Year Four	368
Finance Lease, Liability, Payments, Due Year Five	167
Finance Lease, Liability, Payments, Due after Year Five	0
Finance Lease, Liability, Payment, Due	1,769
Finance Lease, Liability, Undiscounted Excess Amount	182
Finance Lease, Liability	1,587
Lessee, Total Lease, Liability, Payments, Due Year One	11,699
Total Lease, Liability, Payments, Year Two	9,146
Total Lease, Liability, Payments, Year Three	6,223
Total Lease, Liability, Payments, Year Four	3,856
Total Lease, Liability, Payments, Year Five	2,277
Total Lease, Liability, Payments, Due After Year Five	3,175
Total Lease, Liability, Payments Due	36,376
Total Lease, Liability, Undiscounted Excess Amount	3,203
Total Lease, Liability	33,173
Minimum payments for leases not yet commenced	3,946
Operating Lease, Cost	12,910
Finance Lease, Right-of-Use Asset, Amortization	203
Finance Lease, Interest Expense	47
Finance Lease, Cost	250
Short-term Lease, Cost	1,163
Variable Lease, Cost	827
Lease, Cost	15,150
Operating Lease, Payments	12,934
Finance Lease, Interest Payment on Liability	47
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	10,640
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	$ 1,803
Operating Lease, Weighted Average Remaining Lease Term	4 years 3 months 18 days
Finance Lease, Weighted Average Remaining Lease Term	4 years 4 months 24 days
Operating Lease, Weighted Average Discount Rate, Percent	3.90%
Finance Lease, Weighted Average Discount Rate, Percent	5.10%
Operating Leases, Rent Expense	$ 14,073	$ 10,553	$ 7,680
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent

Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Tax Examination [Line Items]
Current Federal Tax Expense (Benefit)	$ (39)	$ (1,330)	$ (2,345)
Deferred Federal Income Tax Expense (Benefit)	9,317	5,908	38,744
Current State and Local Tax Expense (Benefit)	3,657	2,312	1,536
Deferred State and Local Income Tax Expense (Benefit)	(4,195)	(227)	216
Provision for income taxes	8,740	6,663	38,151
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount	10,352	8,430	5,973
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount	1,974	1,277	1,241
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	2,662	2,009	1,193
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	(3,334)	(83)	1,761
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	0	31,333
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	261	0	183
Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount	(75)	(556)	(238)
Effective Income Tax Rate Reconciliation, Tax Contingency, Amount	(1,313)	(3,967)	(1,908)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount	(1,787)	(144)
Effective Income Tax Rate Reconciliation, Tax Settlement, State and Local, Amount	0	0	(1,387)
Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount	$ 0	$ (303)	$ 0
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	24.53%
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Allowance for Doubtful Accounts	$ 592	$ 245
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities	14,619	9,783
Deferred Tax Assets, Operating Loss Carryforwards	22,623	39,045
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Other	1,764	1,396
Deferred Tax Assets, Investments	210	119
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	897	672
Deferred Tax Assets, Capital Loss Carryforwards	74	74
Deferred Tax Assets, Leases	7,681
Deferred Tax Assets, Other	2,444	1,137
Deferred Tax Assets, Gross	50,904	52,471
Deferred Tax Assets, Valuation Allowance	710	4,044
Deferred Tax Assets, Net of Valuation Allowance	50,194	48,427
Deferred Tax Liabilities, Property, Plant and Equipment	517	840
Deferred Tax Liabilities, Goodwill and Intangible Assets	7,926	5,978
Deferred Tax Liabilities, Leasing Arrangements	7,677
Deferred Tax Liabilities, Other	271	735
Deferred Tax Liabilities, Gross	16,391	7,553
Deferred tax assets	33,803	40,874
Operating Loss Carryforwards	217,328
Operating Loss Carryforwards Attributable To Goodwill Amortization	128,044
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	76,055
Reorganization Of Goodwill Excess Tax Basis	14,539
Unrecognized Tax Benefits	26,294	30,256
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions	111	93
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions	29	19
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations	1,573	4,074
Unrecognized Tax Benefits	24,861	26,294	$ 30,256
Increase in Unrecognized Tax Benefits is Reasonably Possible	3,061
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	55	$ 43
State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
Operating Loss Carryforwards Attributable To Goodwill Amortization	$ 6,696

Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
Operating Segments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenues	$ 330,411	$ 293,125	$ 291,277	$ 276,043	$ 293,607	$ 282,633	$ 256,914	$ 243,842	$ 1,190,856	$ 1,076,996	$ 876,828
Cost of services									962,897	894,893	726,866
Gross profit	68,160	$ 58,320	$ 51,264	$ 50,215	50,870	$ 46,397	$ 43,235	$ 41,601	227,959	182,103	149,962
Selling, general and administrative expenses									170,911	140,575	123,920
Goodwill impairment expense	6,976								6,976	0	0
Contingent consideration									(11)	(374)	(103)
Loss (gain) on sale of assets									0	52	(15)
Operating income (loss)									50,083	41,850	25,954
Depreciation and amortization									12,508	9,557	8,860
Capital expenditures									4,745	6,300	4,563
Total assets	560,528				445,258				560,528	445,258	421,994
Communications [Member]
Segment Reporting Information [Line Items]
Revenues									395,141	321,246	219,655
Cost of services									317,013	264,746	179,518
Gross profit									78,128	56,500	40,137
Selling, general and administrative expenses									37,674	31,850	26,003
Goodwill impairment expense									0
Contingent consideration									0	(97)	85
Loss (gain) on sale of assets									8	(6)	(4)
Operating income (loss)									40,446	24,753	14,223
Depreciation and amortization									1,351	1,513	1,247
Capital expenditures									830	973	647
Total assets	154,808				109,263				154,808	109,263	80,528
Residential [Member]
Segment Reporting Information [Line Items]
Revenues									411,790	313,336	285,711
Cost of services									318,034	248,562	227,355
Gross profit									93,756	64,774	58,356
Selling, general and administrative expenses									63,668	46,864	41,401
Goodwill impairment expense									0
Contingent consideration									0	0	0
Loss (gain) on sale of assets									2	(17)	8
Operating income (loss)									30,086	17,927	16,947
Depreciation and amortization									2,276	852	637
Capital expenditures									1,459	1,412	932
Total assets	110,998				63,903				110,998	63,903	55,176
Infrastructure Solutions [Member]
Segment Reporting Information [Line Items]
Revenues									128,379	136,790	97,163
Cost of services									93,358	105,863	75,337
Gross profit									35,021	30,927	21,826
Selling, general and administrative expenses									20,418	18,664	18,293
Goodwill impairment expense									0
Contingent consideration									0	(277)	(288)
Loss (gain) on sale of assets									35	105	18
Operating income (loss)									14,568	12,435	3,227
Depreciation and amortization									6,020	4,528	4,672
Capital expenditures									795	1,377	735
Total assets	124,640				116,867				124,640	116,867	109,506
Commercial and Industrial [Member]
Segment Reporting Information [Line Items]
Revenues									255,546	305,624	274,299
Cost of services									234,492	275,722	244,656
Gross profit									21,054	29,902	29,643
Selling, general and administrative expenses									32,128	27,815	27,031
Goodwill impairment expense									6,976
Contingent consideration									(11)	0	100
Loss (gain) on sale of assets									(45)	(30)	(37)
Operating income (loss)									(17,994)	2,117	2,749
Depreciation and amortization									2,768	2,563	2,197
Capital expenditures									1,362	2,402	2,216
Total assets	68,318				82,050				68,318	82,050	89,729
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Revenues									0	0	0
Cost of services									0	0	0
Gross profit									0	0	0
Selling, general and administrative expenses									17,023	15,382	11,192
Goodwill impairment expense									0
Contingent consideration									0	0	0
Loss (gain) on sale of assets									0	0	0
Operating income (loss)									(17,023)	(15,382)	(11,192)
Depreciation and amortization									93	101	107
Capital expenditures									299	136	33
Total assets	$ 101,764				$ 73,175				$ 101,764	$ 73,175	$ 87,055

Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	May 20, 2019	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	100,000,000	100,000,000
Common Stock, Capital Shares Reserved for Future Issuance	928,669
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	1,500,000			1,000,000.0
Treasury Stock, Shares, Acquired	263,160	467,819
Treasury Stock Acquired, Average Cost Per Share	$ 23.29	$ 17.34
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation	56,806	97,003
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(208,597)	0	0
Shares, Issued	5,750	22,500
Share-based Payment Arrangement, Cash Used to Settle Award	$ 1,100
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 312
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	283,195	0	140,668
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted	69,338	283,195	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(105,000)	0	(140,668)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	38,936	283,195	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 23.57
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	21,750	44,250	45,750
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 6.35	$ 6.39	$ 6.42
Options exercised, shares	5,750	22,500	1,500
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 5.95	$ 6.43	$ 7.21
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	16,000	21,750	44,250
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 6.49	$ 6.35	$ 6.39
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 405	$ 254
2013 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	8,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 5.76
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Remaining Contractual Term	2 years 6 months 29 days
Jan 2015 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	1,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 7.27
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Remaining Contractual Term	4 years 3 months 14 days
Feb 2015 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	7,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 7.21
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Remaining Contractual Term	4 years 4 months 2 days
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 2,441	776	$ 256
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	2,984	0	2,201
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 390	300	$ 189
Performance Based Phantom Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(3,435)
Shares, Issued	90,782
Share-based Payment Arrangement, Expense	$ 1,443	$ 1,151
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted	45,686
Shares, Outstanding	204,501	162,840
Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock, Shares, Acquired	528,563	564,822	133,459
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	113,408	216,679
Shares, Issued	1,287,134	884,518	843,993		712,554
Options exercised, shares	5,750	22,500	1,500
Share-based Payment Arrangement, Nonemployee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Issued	6,789	1,923
Share-based Payment Arrangement, CEO [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Issued		283,195
Share Repurchase Program [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock, Shares, Acquired	263,160	467,819
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	3,000,000.0

Related Party Transactions (Details) $ in Thousands	12 Months Ended
Related Party Transactions (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Related Party Transactions [Abstract]
Related Party Transaction, Purchases from Related Party	$ 8

Employee Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
Employee Benefit Plans (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2019
Retirement Benefits [Abstract]
Defined Contribution Plan, Cost	$ 2,326	$ 2,144	$ 1,895
Liability, Defined Benefit Plan	719	738
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	$ 41	$ 42	$ 0
Defined Benefit Plan, Funded Percentage				83.32%

Fair Value Measurements (Details) - USD ($) $ in Thousands	12 Months Ended
Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Executive Savings Plan assets	$ 766	$ 763
Financial and Nonfinancial Liabilities, Fair Value Disclosure	(644)	(646)
Business Combination, Contingent Consideration, Liability, Noncurrent		(11)
Fair Value, Net Asset (Liability)	122	106
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value	0	11
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	(11)
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Executive Savings Plan assets	766	763
Financial and Nonfinancial Liabilities, Fair Value Disclosure	(644)	(646)
Fair Value, Net Asset (Liability)	$ 122	117
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Business Combination, Contingent Consideration, Liability, Noncurrent		(11)
Fair Value, Net Asset (Liability)		$ (11)

Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Inventory Disclosure [Abstract]
Inventory, Raw Materials, Gross	$ 3,232	$ 4,104
Inventory, Work in Process, Gross	4,894	6,301
Inventory, Finished Goods, Gross	1,186	1,861
Other Inventory, Gross	15,577	9,277
Inventory, Net	$ 24,889	$ 21,543

Goodwill and Intangible Assets Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Goodwill [Line Items]
Goodwill, beginning		$ 50,622	$ 50,702
Goodwill, Acquired During Period		10,117
Goodwill, Written off Related to Sale of Business Unit			(119)
Goodwill, Purchase Accounting Adjustments			39
Impairment expense	$ (6,976)	(6,976)	0	$ 0
Goodwill, ending	53,763	53,763	50,622	50,702
Communications [Member]
Goodwill [Line Items]
Goodwill, beginning		2,816	2,816
Impairment expense		0
Goodwill, ending	2,816	2,816	2,816	2,816
Residential [Member]
Goodwill [Line Items]
Goodwill, beginning		10,018	9,979
Goodwill, Acquired During Period		6,201
Goodwill, Purchase Accounting Adjustments			39
Impairment expense		0
Goodwill, ending	16,219	16,219	10,018	9,979
Infrastructure Solutions [Member]
Goodwill [Line Items]
Goodwill, beginning		30,812	30,931
Goodwill, Acquired During Period		3,916
Goodwill, Written off Related to Sale of Business Unit			(119)
Impairment expense		0
Goodwill, ending	34,728	34,728	30,812	30,931
Commercial and Industrial [Member]
Goodwill [Line Items]
Goodwill, beginning		6,976	6,976
Impairment expense		(6,976)
Goodwill, ending	$ 0	$ 0	$ 6,976	$ 6,976

Goodwill and Intangible Assets Intangibles (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 58,026	$ 39,662
Finite-Lived Intangible Assets, Accumulated Amortization	(18,669)	(13,039)
Intangible Assets, Net (Excluding Goodwill)	39,357	26,623
Amortization of Intangible Assets	6,424	3,950	$ 4,101
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	6,217
Finite-Lived Intangible Assets, Amortization Expense, Year Two	4,634
Finite-Lived Intangible Assets, Amortization Expense, Year Three	4,241
Finite-Lived Intangible Assets, Amortization Expense, Year Four	3,898
Finite-Lived Intangible Assets, Amortization Expense, Year Five	3,571
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	16,796
Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	7,754	5,084
Finite-Lived Intangible Assets, Accumulated Amortization	(1,741)	(1,267)
Intangible Assets, Net (Excluding Goodwill)	$ 6,013	$ 3,817
Trademarks and Trade Names [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years	5 years
Trademarks and Trade Names [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years	20 years
Technical Library
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 400	$ 400
Finite-Lived Intangible Assets, Accumulated Amortization	(141)	(121)
Intangible Assets, Net (Excluding Goodwill)	$ 259	$ 279
Technical Library \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years	20 years
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 46,449	$ 33,539
Finite-Lived Intangible Assets, Accumulated Amortization	(14,900)	(11,051)
Intangible Assets, Net (Excluding Goodwill)	$ 31,549	$ 22,488
Customer Relationships [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	6 years	6 years
Customer Relationships [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years	15 years
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 40	$ 40
Finite-Lived Intangible Assets, Accumulated Amortization	(17)	(9)
Intangible Assets, Net (Excluding Goodwill)	$ 23	$ 31
Noncompete Agreements [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years	5 years
Construction Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 3,383	$ 599
Finite-Lived Intangible Assets, Accumulated Amortization	(1,870)	(591)
Intangible Assets, Net (Excluding Goodwill)	$ 1,513	$ 8
Construction Contracts [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	1 year	1 year

Commitments and Contingencies (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Loss Contingencies [Line Items]
Loss Contingency, Discounted Amount of Insurance-related Assessment Liability	$ 6,254	$ 6,683
Liability for Claims and Claims Adjustment Expense	36	$ 90
Letters of Credit Outstanding, Amount	5,664
Estimated cost of completion of bonded projects	92,856
Insurance Related [Member]
Loss Contingencies [Line Items]
Letters of Credit Outstanding, Amount	5,464
Vendor Related [Member]
Loss Contingencies [Line Items]
Letters of Credit Outstanding, Amount	$ 200

Business Combinations and Divestitures (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Business Combinations [Abstract]
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest	$ 28,952
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets	5,660
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	489
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	331
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	18,276
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	10,117
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities	(3,802)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities	(170)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities, Current	(1,949)
Business Acquisition, Goodwill, Expected Tax Deductible Amount	$ 3,916
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	8 years 9 months 18 days
Business Combination, Acquired Receivable, Fair Value	$ 3,190
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	21,836
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual	812
Business Acquisition, Pro Forma Revenue	1,208,020	$ 1,118,460
Business Acquisition, Pro Forma Net Income (Loss)	$ 43,285	$ 34,967

Quarterly Results of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 330,411	$ 293,125	$ 291,277	$ 276,043	$ 293,607	$ 282,633	$ 256,914	$ 243,842	$ 1,190,856	$ 1,076,996	$ 876,828
Gross profit	68,160	58,320	51,264	50,215	50,870	46,397	43,235	41,601	227,959	182,103	149,962
Net income (loss) attributable to IES Holdings, Inc.	$ 14,606	$ 12,260	$ 6,231	$ 8,502	$ 9,861	$ 10,972	$ 5,489	$ 6,884	$ 41,599	$ 33,206	$ (14,157)
Earnings (loss) per share, basic	$ 0.69	$ 0.58	$ 0.30	$ 0.40	$ 0.47	$ 0.52	$ 0.26	$ 0.32	$ 1.96	$ 1.56	$ (0.67)
Earnings (loss) per share, diluted	$ 0.68	$ 0.58	$ 0.29	$ 0.39	$ 0.46	$ 0.52	$ 0.26	$ 0.32	$ 1.94	$ 1.55	$ (0.67)
Goodwill impairment expense	$ 6,976								$ 6,976	$ 0	$ 0

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(19))
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1337-109256

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=117327953&loc=d3e4984-109258

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(21))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1252-109256

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(23))
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60B
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=117326831&loc=SL5780133-109256

+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=117327953&loc=d3e4984-109258

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1252-109256

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(23))
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1337-109256

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(21))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 60B
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=117326831&loc=SL5780133-109256

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(19))
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details