Per Share Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Earnings Per Share [Abstract]
Undistributed Earnings (Loss) Available to Common Shareholders, Basic	$ 6,926	$ 19,388	$ 15,043	$ 43,797
Noncontrolling Interest, Change in Redemption Value	2,534	(103)	3,464	400
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic	5	16	10	38
Comprehensive income attributable to IES Holdings, Inc.	$ 9,465	$ 19,301	$ 18,517	$ 44,235
Weighted Average Number of Shares Outstanding, Basic	20,718,195	20,829,165	20,730,900	20,780,975
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	221,242	258,614	544,926	285,514
Weighted Average Number of Shares Outstanding, Diluted	20,939,437	21,087,779	21,275,826	21,066,489
Earnings Per Share, Basic	$ 0.33	$ 0.93	$ 0.73	$ 2.11
Earnings Per Share, Diluted	$ 0.33	$ 0.92	$ 0.71	$ 2.08