Consolidated Statement of Stockholders Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]
Balance at Sep. 30, 2017	$ 236,704	$ 220	$ 6,898	$ 196,955	$ 46,427
Balance, shares at Sep. 30, 2017		22,049,529	712,554
Restricted stock grant			$ 5	5
Restricted stock grant, shares			520
Acquisition of treasury stock	(1,230)		$ (1,230)
Acquisition of treasury stock, shares			(79,817)
Options exercised	11		$ 15	4
Options exercised, shares			1,500
Non-cash compensation	(111)			(111)
Increase in noncontrolling interest	44			44
Net income (loss) attributable to IES Holdings, Inc.	(27,348)				(27,348)
Balance at Mar. 31, 2018	208,070	$ 220	$ 8,108	196,835	19,123
Balance, shares at Mar. 31, 2018		22,049,529	790,351
Balance at Dec. 31, 2017	207,509	$ 220	$ 6,881	197,312	16,858
Balance, shares at Dec. 31, 2017		22,049,529	710,784
Restricted stock grant			$ 2	2
Restricted stock grant, shares			250
Acquisition of treasury stock	(1,229)		$ (1,229)
Acquisition of treasury stock, shares			(79,817)
Non-cash compensation	(475)			(475)
Increase in noncontrolling interest	44				44
Net income (loss) attributable to IES Holdings, Inc.	2,221				2,221
Balance at Mar. 31, 2018	208,070	$ 220	$ 8,108	196,835	19,123
Balance, shares at Mar. 31, 2018		22,049,529	790,351
Balance at Sep. 30, 2018	220,407	$ 220	$ 8,937	196,810	32,314
Balance, shares at Sep. 30, 2018		22,049,529	843,993
Issuances under compensation plans			$ 2,323	(2,323)
Issuances under compensation plans, shares			216,679
Restricted stock grant			$ 3,582	(3,582)
Restricted stock grant, shares			283,195
Cumulative effect adjustment from adoption of new accounting standard	102				102
Acquisition of treasury stock	(5,411)		$ (5,411)
Acquisition of treasury stock, shares			(323,563)
Non-cash compensation	(674)			(674)
Increase in noncontrolling interest	0
Net income (loss) attributable to IES Holdings, Inc.	12,373				12,373
Balance at Mar. 31, 2019	228,145	$ 220	$ 8,443	191,579	44,789
Balance, shares at Mar. 31, 2019		22,049,529	667,682
Balance at Dec. 31, 2018	225,231	$ 220	$ 8,896	194,607	39,300
Balance, shares at Dec. 31, 2018		22,049,529	763,426
Issuances under compensation plans			$ 71	(71)
Issuances under compensation plans, shares			3,991
Restricted stock grant			$ 3,582	(3,582)
Restricted stock grant, shares			283,195
Acquisition of treasury stock	(3,200)		$ (3,200)
Acquisition of treasury stock, shares			(191,442)
Non-cash compensation	(625)			(625)
Increase in noncontrolling interest	0
Net income (loss) attributable to IES Holdings, Inc.	5,489				5,489
Balance at Mar. 31, 2019	$ 228,145	$ 220	$ 8,443	$ 191,579	$ 44,789
Balance, shares at Mar. 31, 2019		22,049,529	667,682