INCOME TAXES - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Net operating loss carryforwards	$ 42,337	$ 24,234
Accrued expenses	1,642	1,767
Interest expense	8,334	4,038
Other	1,404	2,712
Total deferred tax assets	53,717	32,751
Less valuation allowance	(42,270)	(24,786)	$ (8,675)
Net deferred tax assets	11,447	7,965
Deferred tax liabilities:
Fixed assets	11,816	8,357
Net deferred tax liabilities	$ (369)	$ (392)