Notes Payable and Indebtedness - Summary of Borrowings (Details) $ in Millions	9 Months Ended
Sep. 30, 2022 USD ($)	Jan. 18, 2022	Dec. 31, 2021 USD ($)
Debt maturing within one year:
Principal amount	$ 32.7		$ 28.1
Debt issuance costs and discount	0.0		0.0
Carrying value	32.7		28.1
Debt maturing after one year:
Principal amount	3,618.0		3,794.8
Debt issuance costs and discount	65.9		78.1
Carrying value	3,552.1		3,716.7
Total debt
Principal amount	3,650.7		3,822.9
Debt issuance costs and discount	65.9		78.1
Carrying value	3,584.8		3,744.8
2026 Term Loan \| Line of Credit \| Secured Debt
Debt maturing within one year:
Principal amount	28.1		28.1
Debt issuance costs and discount	0.0		0.0
Carrying value	28.1		28.1
Debt maturing after one year:
Principal amount	2,658.7		2,754.8
Debt issuance costs and discount	53.0		64.5
Carrying value	2,605.7		2,690.3
2029 Term Loan \| Line of Credit \| Secured Debt
Debt maturing within one year:
Principal amount	4.6		0.0
Debt issuance costs and discount	0.0		0.0
Carrying value	4.6		0.0
Debt maturing after one year:
Principal amount	453.1		0.0
Debt issuance costs and discount	6.7		0.0
Carrying value	446.4		0.0
New Revolving Facility \| Line of Credit \| Revolving Credit Facility
Debt maturing after one year:
Principal amount	46.2		160.0
Debt issuance costs and discount	0.0		0.0
Carrying value	$ 46.2		160.0
Total debt
Maximum ratio of first lien net indebtedness to consolidated EBITDA	6.75
Applicable threshold for maximum ratio of first lien net indebtedness to consolidated EBITDA (as a percent)	35.00%
5.00% Senior Unsecured Notes \| Unsecured Debt Excluding Current Maturities
Debt maturing after one year:
Principal amount	$ 460.0		460.0
Debt issuance costs and discount	6.2		6.8
Carrying value	$ 453.8		453.2
5.00% Senior Unsecured Notes \| Unsecured Debt
Total debt
Interest rate on debt instrument (as a percent)	5.00%
6.875% New Senior Secured Notes \| Secured Debt
Debt maturing after one year:
Principal amount	$ 0.0		420.0
Debt issuance costs and discount	0.0		6.8
Carrying value	0.0		$ 413.2
Total debt
Carrying value	$ 413.3
Interest rate on debt instrument (as a percent)	6.875%	6.875%	6.875%

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Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Noncurrent

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