DEBT - Carrying and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total, carrying value	$ 494,847
First Lien Note Facility, net of unamortized discount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, carrying value	198,000	$ 0
Second Lien Note Facility, net of unamortized discount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, carrying value	82,931	0
2021 Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, carrying value	197,008	$ 196,670
Markets for Identical Item (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrants, fair value	0
Total, fair value	0
Markets for Identical Item (Level 1) | First Lien Note Facility, net of unamortized discount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	0
Markets for Identical Item (Level 1) | Second Lien Note Facility, net of unamortized discount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	0
Markets for Identical Item (Level 1) | 2021 Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrants, fair value	16,908
Total, fair value	475,948
Significant Other Observable Inputs (Level 2) | First Lien Note Facility, net of unamortized discount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	198,000
Significant Other Observable Inputs (Level 2) | Second Lien Note Facility, net of unamortized discount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	82,931
Significant Other Observable Inputs (Level 2) | 2021 Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	178,109
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrants, fair value	0
Total, fair value	0
Significant Unobservable Inputs (Level 3) | First Lien Note Facility, net of unamortized discount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	0
Significant Unobservable Inputs (Level 3) | Second Lien Note Facility, net of unamortized discount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	0
Significant Unobservable Inputs (Level 3) | 2021 Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	0
2017 Warrants | Common Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Warrants, carrying value	16,908
Warrants, fair value	$ 16,900