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Debt - Debt Outstanding (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Mar. 10, 2022	Feb. 15, 2022	Sep. 22, 2020
Debt Instrument [Line Items]
Long-Term Debt, Current Maturities	$ 0.0	$ 449.9
Long-term Debt	943.5	1,391.6
Senior Notes, 3.800 Percent Due February 23, 2032
Debt Instrument [Line Items]
Long-term Debt				$ 395.1
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Long-term Debt			$ 144.7
Senior Notes \| Senior Notes, 4.35 Percent Due February 15, 2025
Debt Instrument [Line Items]
Long-Term Debt, Current Maturities	$ 0.0	449.9
Senior Notes \| Senior Notes, 4.35 Percent Due February 15, 2025
Debt Instrument [Line Items]
Stated interest rate, percentage	4.35%
Senior Notes \| Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Stated interest rate, percentage					2.40%
Long-term Debt	$ 397.9	397.5
Senior Notes \| Senior Notes, 3.800 Percent Due February 23, 2032
Debt Instrument [Line Items]
Stated interest rate, percentage				3.80%
Long-term Debt	396.9	396.5
Junior Debt \| 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Stated interest rate, percentage			5.875%
Long-term Debt	$ 148.7	$ 147.7