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LONG TERM DEBT - November 2019 Refinancing Transactions (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Oct. 21, 2019	Nov. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Nov. 30, 2019	Nov. 01, 2019	Oct. 31, 2019
Line of Credit Facility [Line Items]
Repayments of Second Lien Notes			$ 227,470	$ 0	$ 0
Preferred stock, shares issued (in shares)			1,500,000	0
8.50% Second Lien Notes due 2023
Line of Credit Facility [Line Items]
Notes exchanged	$ 70,800
Series A Preferred Stock
Line of Credit Facility [Line Items]
Preferred stock, shares issued (in shares)						750,000
Liquidation preference	$ 75,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Current borrowing capacity							$ 800,000	$ 425,000
Revolving Credit Facility \| Second Lien Notes due 2023
Line of Credit Facility [Line Items]
Repayments of Second Lien Notes		$ 212,000