Commitments and Contingencies (Details Textual 2) $ in Millions	Sep. 30, 2016 USD ($)
Other Commitments [Line Items]
Loss Contingency Insurance Policy Deductible for Each Line of Coverage Excluding Health	$ 1.0
Loss Contingency Health Insurance Deductible For Qualified Individuals	0.1
Outstanding Performance Bonds	910.1
Estimated Cost to Complete Bonded Projects	$ 71.6