OTHER SUPPLEMENTAL INFORMATION - Total Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Trade receivables	$ 86,592	$ 82,115
Other receivables	4,219	2,104
Total accounts receivable	90,811	84,219
Less: allowance for doubtful accounts	(19,130)	(12)
Total accounts receivable, net	71,681	84,207
Current accounts receivable, net	12,564	6,105
Long-term accounts receivable, net	$ 59,117	$ 78,102