Business Combinations - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended				12 Months Ended
	Apr. 30, 2017	Dec. 31, 2016	Aug. 31, 2016	Jul. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Payment to acquire business, paid with cash on hand					$ 5,596	$ 27,708	$ 12,066
Acquisition and integration costs					$ 900
Nutfield
Business Acquisition [Line Items]
Payment to acquire business, paid with cash on hand	$ 5,496
MWF
Business Acquisition [Line Items]
Payment to acquire business, paid with cash on hand		$ 6,587
LPT
Business Acquisition [Line Items]
Payment to acquire business, paid with cash on hand			$ 17,211
BuildIt
Business Acquisition [Line Items]
Payment to acquire business, paid with cash on hand				$ 3,910