Acquisitions (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Business Acquisition [Line Items]
Purchase price of acquisition, net of cash acquired	$ 7,240	$ 0
Dallas Service Center, Inc.
Business Acquisition [Line Items]
Purchase price of acquisition, net of cash acquired	8,000
Contingent consideration to be paid to seller	$ 800