Document And Entity Information - shares	6 Months Ended
	Mar. 31, 2019	May 02, 2019
Document And Entity Information [Abstract]
Entity Registrant Name	IES Holdings, Inc.
Entity Central Index Key	0001048268
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--09-30
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		21,368,483
Entity Current Reporting Status	Yes
TradingSymbol	IESC
Entity Small Business	true
Entity Emerging Growth Company	false