Long-Term Debt Shelf Arrangements (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Line of Credit Facility [Line Items]
Long-term Debt	$ (1,300.0)
Debt Instrument, Interest Rate, Stated Percentage	6.54%
Debt Instrument, Unused Borrowing Capacity, Amount	$ 255.0
Uncollateralized Senior Note Due April Two Thousand Thirty Two [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ (52.5)	$ (59.5)
Debt Instrument, Interest Rate, Stated Percentage	3.25%
Uncollateralized Senior Note Due August Two Thousand Thirty Nine [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.98%
Uncollateralized Senior Note Due July Two Thousand Thirty Five
Line of Credit Facility [Line Items]
Long-term Debt	$ (50.0)	(50.0)
Debt Instrument, Interest Rate, Stated Percentage	3.00%
Uncollateralized Senior Note Due August Two Thousand Thirty Five
Line of Credit Facility [Line Items]
Long-term Debt	$ (40.0)	$ (40.0)
Debt Instrument, Interest Rate, Stated Percentage	2.96%
Uncollateralized Senior Note Due March 14, 2038
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.43%
Uncollateralized Senior Note Due March 14, 2038 | Prudential [Member]
Line of Credit Facility [Line Items]
Long-term Debt	$ (80.0)