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RELATED PARTY TRANSACTIONS - November 2019 Refinancing Transaction (Details) - USD ($) $ in Thousands					12 Months Ended
	Nov. 22, 2019	Oct. 21, 2019	Apr. 16, 2018	Apr. 10, 2018	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Long-term debt					$ 1,118,161	$ 830,203
Shares issued upon conversion of debt (in shares)					7,200,000
Number of shares issued in transaction (in shares)			3,600,000	58,666,667
8.50% Second Lien Notes due 2023
Related Party Transaction [Line Items]
Notes exchanged		$ 70,800
Second Lien Notes due 2023
Related Party Transaction [Line Items]
Long-term debt					$ 409,482	$ 690,203
Second Lien Notes due 2023 \| Revolving Credit Facility
Related Party Transaction [Line Items]
Long-term debt		200,000
Shares issued upon conversion of debt (in shares)	10,947
Amount of debt converted	$ 1,000
Series A Preferred Stock
Related Party Transaction [Line Items]
Liquidation preference		$ 75,000
Number of shares issued in transaction (in shares)	10,947
Purchase price	$ 1,100