Debt - Interest Rate Swaps (Details)		12 Months Ended
	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) outstanding_contract loan	Dec. 31, 2019 USD ($) outstanding_contract	Dec. 31, 2018 USD ($)	Jun. 22, 2020 USD ($)
Derivative [Line Items]
Number of contracts | outstanding_contract		167	180
Contract notional amount		$ 1,830,063,000	$ 2,004,858,000
Repayments of long-term debt		2,058,469,000	102,579,000	$ 570,972,000
Variable rate debt		200,000,000.0
Senior Notes | Senior Notes Due 2028
Derivative [Line Items]
Aggregate principal amount		$ 800,000,000.0			$ 800,000,000
Secured Debt | Term Loan A | 2016 Credit Facility Agreement
Derivative [Line Items]
Repayments of long-term debt	$ 787,900,000
Interest rate swap
Derivative [Line Items]
Number of contracts | loan		4
Contract notional amount		$ 1,400,000,000
Derivative, term of contract		30 days
Loss on release of interest rate swap recognized in AOCI		$ 104,000,000.0
Interest rate derivative hedge, asset (liability), net		109,200,000	64,800,000
Interest rate swap | Other Expense
Derivative [Line Items]
Loss on release of interest rate swap recognized in earnings		10,300,000
Interest rate swap | Accumulated Other Comprehensive (Loss) Income, Net
Derivative [Line Items]
Interest rate derivative hedge, asset (liability), net		$ 78,100,000	$ 47,200,000
Interest rate swap | Minimum
Derivative [Line Items]
Derivative, fixed interest rate		2.13%
Interest rate swap | Maximum
Derivative [Line Items]
Derivative, fixed interest rate		3.04%