Business Acquisitions Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
	Apr. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Amortization of intangible assets		$ 2,138	$ 2,384	$ 839
Income tax expense		3,757	(8,078)	$ 2,764
PECO and FGC Acquisitions
Business Acquisition [Line Items]
Percentage acquired	100.00%
Total net consideration	$ 8,079
Consideration transferred	8,250
Adjustment to consideration transferred	391
Cash and equivalents	$ 562
Acquisition related costs			59
Cleveland Roll Forming Environmental Division, Inc. d/b/a PECO
Business Acquisition [Line Items]
Discount rate (as a percent)	18.50%
FGC, Inc
Business Acquisition [Line Items]
Discount rate (as a percent)	33.50%
Scenario, Adjustment | PECO and FGC Acquisitions
Business Acquisition [Line Items]
Acquisition related costs		59	0
Amortization of intangible assets		1,449	0
Costs and expense related parties		70	500
Income tax expense		$ 561	$ 242