DEBT - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term debt	$ 467,716
Term Loan Facilities
Debt Instrument [Line Items]
Long-term debt	210,207	$ 222,757
2021 Notes
Debt Instrument [Line Items]
Long-term debt	196,670	$ 196,038
Term loan facilities and 2021 notes
Debt Instrument [Line Items]
Long-term debt	406,877
Fair Value | Fair Value, Inputs, Level 1 | Term Loan Facilities
Debt Instrument [Line Items]
Long-term debt	0
Fair Value | Fair Value, Inputs, Level 1 | 2021 Notes
Debt Instrument [Line Items]
Long-term debt	0
Fair Value | Fair Value, Inputs, Level 1 | Term loan facilities and 2021 notes
Debt Instrument [Line Items]
Long-term debt	0
Fair Value | Fair Value, Inputs, Level 2 | Term Loan Facilities
Debt Instrument [Line Items]
Long-term debt	195,493
Fair Value | Fair Value, Inputs, Level 2 | 2021 Notes
Debt Instrument [Line Items]
Long-term debt	147,502
Fair Value | Fair Value, Inputs, Level 2 | Term loan facilities and 2021 notes
Debt Instrument [Line Items]
Long-term debt	342,995
Fair Value | Fair Value, Inputs, Level 3 | Term Loan Facilities
Debt Instrument [Line Items]
Long-term debt	0
Fair Value | Fair Value, Inputs, Level 3 | 2021 Notes
Debt Instrument [Line Items]
Long-term debt	0
Fair Value | Fair Value, Inputs, Level 3 | Term loan facilities and 2021 notes
Debt Instrument [Line Items]
Long-term debt	$ 0