Annual report pursuant to Section 13 and 15(d)

Acquisitions - Schedule of Assets Acquired and Liabilities Assumed, RTS (Details)

v3.19.1
Acquisitions - Schedule of Assets Acquired and Liabilities Assumed, RTS (Details) - USD ($)
$ in Thousands
Dec. 31, 2018
Jun. 15, 2018
Dec. 31, 2017
Dec. 31, 2016
Business Acquisition [Line Items]        
Goodwill $ 101,245   $ 99,811 $ 88,727
RTS Energy Services LLC        
Business Acquisition [Line Items]        
Inventories   $ 180    
Property, plant and equipment   7,787    
Goodwill   133    
Total assets acquired   $ 8,100