LONG-TERM DEBT - Aggregate Contractual Maturities of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
2019	$ 13,750
2020	13,750
2021	13,750
2022	1,004,489
2023	452,500
2024	400,000
2027	450,000
Total long-term debt	2,348,239
Less: Current portion of long-term debt	13,750	$ 13,750
Less: unamortized original issue discount	61,377
Less: unamortized debt issuance costs	27,564
Long-term debt, net	$ 2,245,548	$ 1,979,469

Long-term Debt, Maturities, Repayments of Principal after Year Six

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Long-term Debt, Maturities, Repayments of Principal in Year Six

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Amount, after accumulated amortization, of debt discount (premium).

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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, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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