Debt (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2018	Dec. 31, 2019	Jun. 07, 2018
Debt Instrument [Line Items]
Amortization of deferred financing costs	$ 1,200,000	$ 1,300,000	$ 2,400,000	$ 2,500,000
Remaining unamortized deferred financing costs	13,400,000		13,400,000			$ 15,800,000
Credit Agreement
Debt Instrument [Line Items]
Payments of financing costs					$ 53,100,000
Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity							$ 1,000,000,000.0
Letters of credit, amount outstanding	1,000,000.0		1,000,000.0
Credit Agreement | Senior Secured Term Loan | Line of Credit
Debt Instrument [Line Items]
Debt instrument, principal amount							$ 2,612,500,000
Debt Instrument, quarterly payment as a percent of total borrowings							5.00%
Debt Instrument, Periodic Payment	(32,700,000)		(65,300,000)
Outstanding debt	$ 2,449,200,000		$ 2,449,200,000