Employee Benefit Plans (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2015 USD ($) years	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)
Executive Saving Plan [Abstract]
Maximum percentage of salary permitted for deferral	75.00%
Post Retirement Benefit Plan [Abstract]
Defined Benefit Plan, Percentage Vest After Ten Years Of Service	50.00%
Denfied Benefits Plan, Annual Percentage Vested	10.00%
Defined Benefit Plan, Plans with Benefit Obligations in Excess of Plan Assets, Aggregate Benefit Obligation	$ 871	$ 853
Multiemployer Plans [Abstract]
Percentage of Plan Funded	84.75%
IES 401(k) Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Benefit Plan Plans Fully Vested Number Of Years | years	3
Defined Benefit Plan Minimum Age | years	21
Minimum Employment Term For Eligibility	60 days
401(k) Matching Expense	$ 288	276	$ 177
Infrastructure Solutions 401(k) Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
401(k) Matching Expense	$ 99	$ 74	$ 4