Long-Term Indebtedness - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Summary of Long-term debt
Net discount	$ (6,455)	$ (6,792)
Deferred financing costs	(1,493)	(1,793)
Total debt	2,229,557	2,106,512
Less current portion	(165,000)	(43,000)
Total long-term debt	2,064,557	2,063,512
Amended and Restated Term Loan B, 2024 Notes, 2027 Notes
Summary of Long-term debt
Deferred financing costs	(12,738)	(13,446)
Amended and Restated Term Loan B, As Amended March 2018
Summary of Long-term debt
Long-term debt	583,750	583,750
Senior Unsecured 2024 Notes
Summary of Long-term debt
Long-term debt	1,000,000	1,000,000
Senior Unsecured 2027 Notes
Summary of Long-term debt
Long-term debt	$ 500,000	$ 500,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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