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.

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Nominal or face amount used to calculate payment on derivative.

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

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Financial Instruments and Fair Value Measurements - Summary of Derivative Financial Instruments (Details) £ in Millions, $ in Millions	Jun. 30, 2022 USD ($) derivative Rate	Dec. 31, 2021 USD ($)	Feb. 29, 2020 derivative	May 31, 2019 GBP (£) derivative	May 31, 2019 USD ($) derivative
Derivative [Line Items]
Notional Amount	$ 1,760.7	$ 2,731.9
Fair Value - asset (liability)	105.1	(41.1)
Designated as hedging instrument \| Cash flow hedge
Derivative [Line Items]
Notional Amount	927.5	1,092.4
Fair Value - asset (liability)	$ 68.2	(26.4)
Interest rate swap \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative	1
Interest rate swap \| Designated as hedging instrument \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative	1
Notional Amount	$ 250.0	250.0
Weighted Average Strike Rate	2.88%
Fair Value - asset (liability)	$ 0.4	(11.9)
Cross-currency swaps \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative				4	4
Notional Amount				£ 130	$ 166.0
Cross-currency swaps \| Designated as hedging instrument \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative	0
Notional Amount	$ 0.0	166.3
Fair Value - asset (liability)	$ 0.0	(13.8)
GBP cross-currency swaps \| Designated as hedging instrument \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative	4
Notional Amount	$ 166.3
Foreign currency forwards \| Designated as hedging instrument \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative	36
Notional Amount	$ 177.5	176.1
Fair Value - asset (liability)	$ 20.4	7.6
Weighted average forward exchange rate \| Rate	140.00%
Forward-starting swaps \| Designated as hedging instrument \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative	6
Forward-starting swap, derivative \| Designated as hedging instrument \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative	4
Notional Amount	$ 300.0	300.0
Weighted Average Strike Rate	1.86%
Fair Value - asset (liability)	$ 31.2	(3.2)
Forward-starting swaps, hybrid debt \| Designated as hedging instrument \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative	2
Notional Amount	$ 200.0	200.0
Weighted Average Strike Rate	1.93%
Fair Value - asset (liability)	$ 16.2	(5.1)
Currency exchange swaps \| Not designated as hedging instrument
Derivative [Line Items]
Number of Instruments \| derivative	5
Notional Amount	$ 833.2	1,639.5
Fair Value - asset (liability)	$ 36.9	$ (14.7)
GBP currency exchange swap \| Not designated as hedging instrument
Derivative [Line Items]
Number of Instruments \| derivative	3
Notional Amount	$ 564.9
Weighted average forward exchange rate \| Rate	126.00%
EUR currency exchange swap \| Not designated as hedging instrument
Derivative [Line Items]
Number of Instruments \| derivative	2
Notional Amount	$ 268.3
Weighted average forward exchange rate \| Rate	111.00%
Treasury rate locks \| Designated as hedging instrument \| Cash flow hedge
Derivative [Line Items]
Number of Instruments \| derivative			5