Debt - Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total debt, net of discounts	$ 2,922,600	$ 2,919,185
Senior Notes | 5.875% Senior Notes due 2022
Debt Instrument [Line Items]
Total debt, net of discounts	1,088,734	1,087,351
Term B Loans | Senior Secured Credit Agreement
Debt Instrument [Line Items]
Total debt, net of discounts	188,038	187,725
Term C Loans | Senior Secured Credit Agreement
Debt Instrument [Line Items]
Total debt, net of discounts	$ 1,645,828	$ 1,644,109