Derivatives - Derivative Instruments Effect on AOCI and Results of Operations (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain/(Loss) Recognized in AOCI on Derivatives, Net of Tax	$ 19.9	$ 1.3	$ 50.0	$ 3.3
Derivatives Designated in Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Total gain/(loss)	19.9	3.2	91.8	10.4
Loss Reclassified from AOCI	(3.0)	(0.4)
Interest rate contracts - cash flow hedge \| Derivatives Designated in Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Loss Reclassified from AOCI			(4.6)	(2.0)
Foreign exchange contracts \| Interest rate contracts - cash flow hedge \| Derivatives Designated in Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain/(Loss) Recognized in AOCI on Derivatives, Net of Tax	0.0	(0.2)	0.0	(0.1)
Loss Reclassified from AOCI	0.0	(0.3)	0.0	(1.3)
Foreign exchange contracts \| Interest rate contracts - cash flow hedge \| Derivatives Designated in Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain/(Loss) Recognized in AOCI on Derivatives, Net of Tax	0.1	(0.4)	0.3	(0.5)
Loss Reclassified from AOCI	0.0	(0.1)	(0.1)	(0.7)
Interest rate contracts \| Interest rate contracts - cash flow hedge \| Derivatives Designated in Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain/(Loss) Recognized in AOCI on Derivatives, Net of Tax	19.7	1.9	47.8	3.9
Loss Reclassified from AOCI	(3.0)	0.0	(4.5)	0.0
Foreign exchange contracts \| Foreign exchange contracts - net investment hedge \| Derivatives Designated in Hedging Relationships
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain/(Loss) Recognized in AOCI on Derivatives, Net of Tax	$ 0.1	$ 1.9	$ 43.7	$ 7.1

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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