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Debt - Additional Information (Details) - USD ($) $ in Millions							12 Months Ended
	Oct. 08, 2021	Sep. 21, 2021	Nov. 21, 2019	Dec. 13, 2017	Sep. 05, 2014	Oct. 22, 2013	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Oct. 31, 2021
Debt Instrument [Line Items]
Redeemed Value of Notes							$ 2,491.5	$ 2,491.0
Annual Principal Maturities for Debt [Abstract]
2023							0.0
2024							400.0
2025							0.0
2026 and thereafter							2,100.0
Interest payments							85.6	149.6	$ 97.0
Estimated interest payments for 2023							84.2
Estimated interest payments for 2024							84.2
Estimated interest payments for 2025							69.6
Estimated interest payments for 2026							968.4
Amortization of financing costs							1.6	3.4	$ 2.0
Write-off of deferred debt issuance costs							1.4
Unsecured Revolving Credit Facility
Debt Instrument [Line Items]
Redeemed Value of Notes							$ 350.0
Debt instrument, term							5 years
Debt instrument, maturity date							Aug. 29, 2021
Debt instrument offering date							Jun. 08, 2021
Line of Credit
Debt Instrument [Line Items]
Redeemed Value of Notes							$ 0.0	0.0
Unused borrowing capacity								$ 321.3
4.05% Senior Notes, due December 2049 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount			$ 400.0
Stated interest rate			4.05%
Debt instrument, maturity date			Dec. 15, 2049					Dec. 15, 2049	Dec. 15, 2049
3.65% Senior Notes, due September 2024
Debt Instrument [Line Items]
Stated interest rate										4.50%
Debt instrument, redemption amount included premiums, accrued and unpaid interest										$ 769.8
3.65% Senior Notes, due September 2024 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount		$ 700.0
Redeemed Value of Notes							$ 399.8	$ 399.6
Stated interest rate	4.50%	4.50%					3.65%	3.65%
Debt instrument, maturity date		Nov. 01, 2023				Nov. 01, 2023		Nov. 01, 2023	Nov. 01, 2023
Debt instrument, repurchase amount	$ 769.8
Debt instrument, redemption premium	56.1
Debt instrument, accrued and unpaid interest	13.7
Annual Principal Maturities for Debt [Abstract]
Write-off of deferred debt issuance costs	1.4
Write-off unamortized debt discount	$ 0.5						$ 0.2	$ 0.4
3.40% Senior Notes, due December 2027 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount					$ 400.0
Redeemed Value of Notes							$ 499.1	$ 499.0
Stated interest rate					3.65%		3.40%	3.40%
Debt instrument, maturity date					Sep. 15, 2024			Sep. 15, 2024	Sep. 15, 2024
Annual Principal Maturities for Debt [Abstract]
Write-off unamortized debt discount							$ 0.9	$ 1.0
3.00% Senior Notes, due December 2029 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount			$ 500.0	$ 500.0
Redeemed Value of Notes							$ 499.5	$ 499.5
Stated interest rate			3.00%	3.40%			3.00%	3.00%
Debt instrument, maturity date			Dec. 15, 2029	Dec. 15, 2027				Dec. 15, 2027	Dec. 15, 2027
Annual Principal Maturities for Debt [Abstract]
Write-off unamortized debt discount							$ 0.5	$ 0.5
Fixed-Rate Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Book value of fixed rate debt							2,491.5
Long-term debt (fixed-rate debt), fair value							2,041.2
3.05% Senior Notes, due October 2051 \| Senior Notes
Debt Instrument [Line Items]
Debt, face amount		$ 700.0
Redeemed Value of Notes							$ 696.4	$ 696.3
Stated interest rate		3.05%					3.05%	3.05%
Debt instrument, maturity date		Dec. 31, 2051
Debt issuance costs								$ 7.7
Annual Principal Maturities for Debt [Abstract]
Write-off unamortized debt discount							$ 3.6	$ 3.7
3.05% Senior Notes, due October 2021
Debt Instrument [Line Items]
Stated interest rate										3.05%
3.05% Senior Notes, due October 2021 \| Senior Notes
Debt Instrument [Line Items]
Debt instrument, maturity date		Oct. 01, 2051
Redemption Premiums
Annual Principal Maturities for Debt [Abstract]
Interest payments							$ 56.1