OTHER ASSETS - Summarized Financial Information, Equity Method Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity Method Investment, Summarized Financial Information, Income Statement [Abstract]
Revenues, net	$ 145,253	$ 115,054	$ 82,524
Operating (loss) income	(58,359)	(17,470)	7,804
Net loss	(81,596)	(41,926)	$ (2,285)
Equity Method Investment, Summarized Financial Information, Assets And Liabilities [Abstract]
Current assets	27,961	31,602
Noncurrent assets	710,831	777,619
Current liabilities	52,527	27,864
Noncurrent liabilities	$ 543,604	$ 550,260

Equity Method Investment, Summarized Financial Information, Assets And Liabilities [Abstract]

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The amount of current assets reported by an equity method investment of the entity.

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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