Debt and Other Long-Term Obligations - Summary of Outstanding Debt and Other Long Term Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Total Debt:
Current portion of long-term debt	$ 4,875
Total long-term debt	2,170,125	$ 2,175,000
Less: Deferred financing costs	(51,796)	(58,789)
Total debt, net of deferred financing costs	2,123,204	2,116,211
Other long-term obligations:
Other long-term obligations	199,874	197,728
Term Loan Secured Due 2024
Total Debt:
Total long-term debt	970,125	975,000
6.875% Senior, Unsecured Notes Due 2022
Total Debt:
Total long-term debt	700,000	700,000
7.125% Senior, Unsecured Notes Due 2025
Total Debt:
Total long-term debt	$ 500,000	$ 500,000