LONG-TERM DEBT / INTEREST EXPENSE - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument
Total debt	$ 1,297,023	$ 1,540,453
Debt issuance costs	(1,285)	(2,306)
Less: current maturities	0	(12,562)
Long-term debt	1,297,023	1,527,891
Term Loan Facility
Debt Instrument
Unamortized discount	900	1,600
Total debt	1,130,320	1,170,486
Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument
Total debt	0	127,000
Notes \| Notes
Debt Instrument
Unamortized discount	18,065	37,179
Total debt	$ 167,988	$ 245,273

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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Amount, after accumulated amortization, of debt discount.

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-SubTopic 30
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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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