Quarterly Results Of Operations (Tables)

12 Months Ended

Sep. 30, 2018

Quarterly Results Of Operations (Unaudited) [Abstract]

Quarterly Financial Information [Table Text Block]

		Year Ended September 30, 2018
		First		Second		Third		Fourth
		Quarter		Quarter		Quarter		Quarter
Revenues		$	198,300	$	205,677	$	232,576	$	240,275
Gross profit		$	33,064	$	33,840	$	42,537	$	40,521
Net income (loss) attributable to IES Holdings, Inc.		$	(29,569)	$	2,221	$	8,516	$	4,675
Earnings (loss) per share:
	Basic	$	(1.39)	$	0.11	$	0.40	$	0.22
	Diluted	$	(1.39)	$	0.11	$	0.40	$	0.22

		Year Ended September 30, 2017
		First		Second		Third		Fourth
		Quarter		Quarter		Quarter		Quarter
Revenues		$	192,178	$	203,662	$	208,323	$	206,581
Gross profit		$	35,182	$	31,814	$	35,398	$	38,104
Net income attributable to IES Holdings, Inc.		$	3,872	$	536	$	5,868	$	3,146
Earnings per share:
	Basic	$	0.18	$	0.02	$	0.27	$	0.15
	Diluted	$	0.18	$	0.02	$	0.27	$	0.14