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Derivative Instruments and Hedging Activities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Feb. 15, 2022
Included in Condensed Consolidated Statement of Operations	$ (0.1)	$ (5.7)
Included in Other Comprehensive Income (Loss)	1.7	(3.0)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0.0	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(41.2)	(42.8)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0.0	0.0
Derivative Assets (Liabilities), at Fair Value, Net	0.0
Gain (Loss) on Derivative Instruments, Net, Pretax	0.1
Not Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net	4.5		$ 1.7
Not Designated as Hedging Instrument \| Reverse Treasury Lock
Derivative, Notional Amount	0.0		100.0
Not Designated as Hedging Instrument \| Treasury Lock
Derivative, Notional Amount	100.0		0.0
Equity Securities
Included in Condensed Consolidated Statement of Operations	(0.5)	0.0
Included in Other Comprehensive Income (Loss)	0.0	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0.0	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0.0	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0.0	0.0
Redeemable Preferred Stocks
Included in Condensed Consolidated Statement of Operations	0.0	0.0
Included in Other Comprehensive Income (Loss)	0.0	(0.5)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0.0	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0.0	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		$ 0.0
Senior Notes, 3.800 Percent Due February 23, 2033 \| Senior Notes
Stated interest rate				3.80%
Fair Value Hedging \| Designated as Hedging Instrument
Derivative Assets (Liabilities), at Fair Value, Net	3.5		0.4
Fair Value Hedging \| Designated as Hedging Instrument \| Interest Rate Swap
Derivative, Notional Amount	0.0		5.0
Fair Value Hedging \| Designated as Hedging Instrument \| Treasury Lock
Derivative, Notional Amount	$ 100.0		$ 0.0