Derivative Instruments - Schedule of Derivative Financial Instruments (Details) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2026 USD ($) derivative Rate	Dec. 31, 2025 USD ($) derivative
Derivative [Line Items]
Notional Amount	$ 7,898.1	$ 6,597.5
Fair Value - asset (liability)	(64.7)	(197.7)
Designated as hedging instrument
Derivative [Line Items]
Notional Amount	3,608.2	3,624.7
Fair Value - asset (liability)	(83.7)	(150.7)
Not designated as hedging instrument
Derivative [Line Items]
Notional Amount	4,289.9	2,972.8
Fair Value - asset (liability)	$ 19.0	(47.0)
Interest rate swaps \| Designated as hedging instrument
Derivative [Line Items]
Number of Instruments \| derivative	7
Notional Amount	$ 1,400.0	2,105.0
Weighted Average Strike Rate	3.13%
Fair Value - asset (liability)	$ 22.2	5.1
Cross-currency swaps \| Designated as hedging instrument \| Fair value hedge
Derivative [Line Items]
Number of Instruments \| derivative	11
Notional Amount	$ 1,220.0	720.0
Fair Value - asset (liability)	$ (64.8)	(81.0)
Cross-currency swaps \| Designated as hedging instrument \| Net investment hedge
Derivative [Line Items]
Number of Instruments \| derivative	3
Notional Amount	$ 280.0	280.0
Fair Value - asset (liability)	$ (55.7)	(66.1)
Cross-currency swaps \| Not designated as hedging instrument
Derivative [Line Items]
Number of Instruments \| derivative	4
Notional Amount	$ 500.0	0.0
Fair Value - asset (liability)	$ (4.5)	0.0
Currency Swap, USD \| Designated as hedging instrument \| Fair value hedge
Derivative [Line Items]
Weighted Average Strike Rate	5.625%
Currency Swap, USD \| Designated as hedging instrument \| Net investment hedge
Derivative [Line Items]
Weighted Average Strike Rate	5.625%
Currency Swap, USD \| Not designated as hedging instrument
Derivative [Line Items]
Weighted Average Strike Rate	4.75%
Currency Swap, EUR \| Designated as hedging instrument \| Fair value hedge
Derivative [Line Items]
Weighted Average Strike Rate	4.681%
Currency Swap, EUR \| Designated as hedging instrument \| Net investment hedge
Derivative [Line Items]
Weighted Average Strike Rate	4.716%
Currency Swap, EUR \| Not designated as hedging instrument
Derivative [Line Items]
Weighted Average Strike Rate	3.806%
Currency Swap, USD \| Designated as hedging instrument \| Fair value hedge
Derivative [Line Items]
Weighted Average Strike Rate	3.95%
Currency Swap, GBP \| Designated as hedging instrument \| Fair value hedge
Derivative [Line Items]
Weighted Average Strike Rate	4.392%
Currency Swap, USD \| Designated as hedging instrument \| Fair value hedge
Derivative [Line Items]
Weighted Average Strike Rate	4.91%
Currency Swap, EUR \| Designated as hedging instrument \| Fair value hedge
Derivative [Line Items]
Weighted Average Strike Rate	4.122%
Foreign currency forwards \| Designated as hedging instrument
Derivative [Line Items]
Number of Instruments \| derivative	65
Notional Amount	$ 708.2	519.7
Fair Value - asset (liability)	$ 14.6	(8.7)
Foreign currency forward, GBP \| Designated as hedging instrument
Derivative [Line Items]
Weighted average forward exchange rate \| Rate	134.00%
Foreign currency forward, EUR \| Designated as hedging instrument
Derivative [Line Items]
Weighted average forward exchange rate \| Rate	121.00%
Currency exchange swaps \| Not designated as hedging instrument
Derivative [Line Items]
Number of Instruments \| derivative	7
Notional Amount	$ 3,789.9	2,972.8
Fair Value - asset (liability)	$ 23.5	$ (47.0)
GBP currency exchange swap \| Not designated as hedging instrument
Derivative [Line Items]
Weighted average forward exchange rate \| Rate	133.00%
EUR currency exchange swap \| Not designated as hedging instrument
Derivative [Line Items]
Weighted average forward exchange rate \| Rate	87.00%
Variable to fixed interest rate swap
Derivative [Line Items]
Number of derivative instruments entered into \| derivative		5
Number of derivative instruments assumed with merger \| derivative	2

Derivative, Number Of Instruments Assumed With Merger

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Derivative, Number Of Instruments Entered Into

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

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-Topic 820
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- Definition

Average contractual rate at which a foreign currency can be purchased or sold.

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No definition available.

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- Definition

Average fixed interest rate that will be received or paid upon exercise of a group of interest rate swaption contracts.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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-Topic 815
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Nominal or face amount used to calculate payment on derivative.

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- Definition

The number of derivative instruments of a particular group held by the entity.

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