Business Acquisition - Recognized Identified Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Apr. 09, 2017	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill		$ 0	$ 69,483
Contingent consideration		$ (456)
Tony Bagliore Concrete, Inc. (TBC)
Business Acquisition [Line Items]
Accounts receivable	$ 3,239
Retainage	1,860
Fixed assets, net	2,098
Other	9
Goodwill	2,562
Other intangible assets	878
Accounts payable	(2,017)
Accrued expenses and other current liabilities	(1,080)
Contingent consideration	(456)
Deferred tax liability	(1,093)
Total Acquisition Consideration, Final	6,000
Working capital adjustment (all attributable to Goodwill)	557
Total Acquisition Consideration	$ 6,557