Debt and Other Long-Term Obligations - Summary of Outstanding Debt and Other Long Term Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Total Debt:
Current portion of long-term debt	$ 2,438
Long-term debt	2,230,563	$ 2,175,000
Less: Deferred financing costs	(54,155)	(58,789)
Long-term debt	2,176,408	2,116,211
Other long-term obligations:
Other long-term obligations	211,968	197,728
Term Loan Secured Due 2024
Total Debt:
Long-term debt	972,563	975,000
6.875% Senior, Unsecured Notes Due 2022
Total Debt:
Long-term debt	700,000	700,000
7.125% Senior, Unsecured Notes Due 2025
Total Debt:
Long-term debt	500,000	$ 500,000
Credit Agreement
Total Debt:
Long-term debt	$ 58,000

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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