Derivative Instruments and Hedging Activities (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Feb. 15, 2022
Gain (Loss) on Derivative Used in Net Investment Hedge, after Tax	$ (5.0)	$ 0.0	$ (1.1)	$ 0.0
Gain (Loss) on Derivative Used in Net Investment Hedge, after Tax	4.7	0.0	1.1	0.0
Gain (Loss) on Hedging Activity	(0.3)	0.0	0.0	0.0
Included in Condensed Consolidated Statement of Operations	(6.3)	1.2	(12.2)	1.2
Included in Other Comprehensive Income (Loss)	(3.3)	4.6	(15.1)	5.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0.0	0.0	0.0	(0.1)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(62.3)	(38.4)	(127.9)	(104.6)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0.0	(211.7)	(5.7)	(212.3)
Derivative Assets (Liabilities), at Fair Value, Net	0.3		0.3
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	0.0	0.0	0.0	0.0
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax	(0.3)	0.0	(0.3)	0.0
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax	(0.3)	0.0	(0.3)	0.0
Equity Securities
Included in Condensed Consolidated Statement of Operations	0.0	0.3	0.0	0.3
Included in Other Comprehensive Income (Loss)	0.0	0.0	0.2	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0.0	0.0	0.0	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(1.9)	0.0	(1.9)	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0.0		0.0	(2.6)
Redeemable Preferred Stocks
Included in Condensed Consolidated Statement of Operations	0.0	0.0	0.0	0.0
Included in Other Comprehensive Income (Loss)	(0.1)	(0.1)	(1.3)	(0.1)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0.0	0.0	0.0	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0.0	0.0	0.0	0.0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		$ 0.0	0.0	$ 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 \| Interest Rate Swap
Derivative, Notional Amount	$ 5.0		$ 5.0

Contractual interest rate for funds borrowed, under the debt agreement.

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Gain (loss) incurred in hedging activities.

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