OTHER SUPPLEMENTAL INFORMATION (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
OTHER SUPPLEMENTAL INFORMATION.
Accrued workers compensation	$ 1,505	$ 1,911
Accrued taxes	2,013	1,486
Accrued fabricator and other job cost	16,114	11,230
Accrued liquidated damages	4,400	6,574
Contract loss provision	5,336	834
Accrued legal and professional fees	1,456	992
Accrued interest expense	1,045	576
Derivative liabilities	748
Other accrued expenses	1,298	5,002
Total	$ 33,915	$ 28,605