Acquisitions (Details Textual) - USD ($) $ in Millions		1 Months Ended
	Apr. 13, 2015	Nov. 24, 2015
E.S. Boulos Company [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred, Total	$ 11.4
High Country Line Construction Inc [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred, Total		$ 1.7
Business Acquisition, Transaction Costs		0.2
Goodwill, Acquired During Period		0.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		$ 0.3