Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment
Stockholders' Equity Attributable to Parent, Beginning Balance at Sep. 30, 2019	$ 246,248		$ 220	$ 12,483	$ 192,911	$ 65,600
Shares, Issued, Beginning Balance at Sep. 30, 2019			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				(528,563)
Options exercised	(34)			$ (84)	(50)
Options exercised, shares				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			22,049,529	1,287,134
Issuances under compensation plans	0			$ (2,737)	(2,737)
Issuances under compensation plans, shares				140,660
Acquisition of treasury stock	$ (7,011)			$ (7,538)	527
Acquisition of treasury stock, shares	(124,205)			(170,524)
Options exercised	$ 0			$ 0	0
Options exercised, shares				0
Non-cash compensation	3,522				3,522
Cumulative Effect of New Accounting Principle	(315)
Decrease (increase) in noncontrolling interest						(315)
Net income (loss) attributable to IES Holdings, Inc.	66,658					66,658
Stockholders' Equity Attributable to Parent, Ending Balance at Sep. 30, 2021	345,953	$ 214	$ 220	$ 29,300	201,899	173,134	$ 214
Shares, Issued, Ending Balance at Sep. 30, 2021			22,049,529	1,316,998
Issuances under compensation plans	0			$ (3,638)	(3,638)
Issuances under compensation plans, shares				157,167
Acquisition of treasury stock	$ (18,556)			$ (18,556)	0
Acquisition of treasury stock, shares	(511,600)			(556,798)
Options exercised	$ (53)			$ (218)	(165)
Options exercised, shares				9,000
Non-cash compensation	3,775				$ 3,775
Decrease (increase) in noncontrolling interest	(4,699)					(4,699)
Net income (loss) attributable to IES Holdings, Inc.	34,762					$ 34,762
Stockholders' Equity Attributable to Parent, Ending Balance at Sep. 30, 2022	$ 361,288		$ 220				$ 214
Shares, Issued, Ending Balance at Sep. 30, 2022	9,000		22,049,529	1,707,629