Debt - Long-term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total debt, net of discounts	$ 2,927,791	$ 2,926,083
Senior Notes | 5.875% Senior Notes due 2022
Debt Instrument [Line Items]
Total debt, net of discounts	1,090,826	1,090,139
Term B Loans | Senior Secured Credit Agreement
Debt Instrument [Line Items]
Total debt, net of discounts	188,514	188,357
Term C Loans | Senior Secured Credit Agreement
Debt Instrument [Line Items]
Total debt, net of discounts	$ 1,648,451	$ 1,647,587