Debt - Long Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Mar. 10, 2022	Feb. 15, 2022
Debt Instrument [Line Items]
Non-Current:	$ 1,390.9	$ 1,389.2
Senior Notes | Senior Notes, 4.35 Percent Due February 15, 2025
Debt Instrument [Line Items]
Current:	449.9	0.0
Non-Current:	$ 0.0	449.6
Stated interest rate	4.35%
Senior Notes | Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Non-Current:	$ 397.4	397.0
Stated interest rate	2.40%
Senior Notes | Senior Notes, 3.800 Percent Due February 23, 2033
Debt Instrument [Line Items]
Non-Current:	$ 396.3	396.0		$ 395.1
Stated interest rate	3.80%
Junior Debt | 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Non-Current:	$ 147.3	$ 146.6	$ 144.7
Stated interest rate	5.875%