FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS - Schedule of Carrying Amount and Estimated Fair Values of the Financial Instruments (Details) - Level 2 - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Interest rate swaps | Carrying Amount
Actual and estimated fair values of the financial instruments
Interest rate swaps	$ 596	$ 0
Interest rate swaps | Fair Value
Actual and estimated fair values of the financial instruments
Interest rate swaps	596	0
FILO Asset-based Term Loan Facility | Asset-backed Securities | Carrying Amount
Actual and estimated fair values of the financial instruments
Long-term debt	263,403	0
FILO Asset-based Term Loan Facility | Asset-backed Securities | Fair Value
Actual and estimated fair values of the financial instruments
Long-term debt	269,330	0
1.5% Convertible Senior Notes, Due 2020 | Notes | Carrying Amount
Actual and estimated fair values of the financial instruments
Long-term debt	173,591	167,988
1.5% Convertible Senior Notes, Due 2020 | Notes | Fair Value
Actual and estimated fair values of the financial instruments
Long-term debt	135,184	85,044
Tranche B-1 | Amended Term Loan Facility Due March 2021 | Term Loan Facility | Carrying Amount
Actual and estimated fair values of the financial instruments
Long-term debt	148,402	1,130,320
Tranche B-1 | Amended Term Loan Facility Due March 2021 | Term Loan Facility | Fair Value
Actual and estimated fair values of the financial instruments
Long-term debt	146,176	930,592
Tranche B-2 | Amended Term Loan Facility Due March 2021 | Term Loan Facility | Carrying Amount
Actual and estimated fair values of the financial instruments
Long-term debt	647,366	0
Tranche B-2 | Amended Term Loan Facility Due March 2021 | Term Loan Facility | Fair Value
Actual and estimated fair values of the financial instruments
Long-term debt	$ 642,511	$ 0