ACQUISITIONS - GRR Acquisition (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 10, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
ACQUISITION
Goodwill		$ 273,421	$ 12,242	$ 150,771
GRR Acquisition
ACQUISITION
Miles of layflat hose	1,200
Total consideration paid	$ 59,638
Cash paid	53,032
Class A Common Stock (274,998 shares)	$ 5,500
Class A Common stock issued, Share Price	$ 20.00
Cash on hand	$ 19,000
Proceeds from credit facility	34,000
Transaction cost	1,000
Goodwill	$ 12,049