Financial Instruments, Risk Management and Fair Value Measurements - Fair Value of Derivatives by Balance Sheet Location (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Derivative Asset [Abstract]
Total Gross Amounts	$ 29.9	$ 47.0
Gross Amounts Subject to Master Netting Arrangements	(29.6)	(12.9)
Net Amounts	0.3	34.1
Derivative Liability [Abstract]
Total Gross Amounts	(69.2)	(12.9)
Gross Amounts Subject to Master Netting Arrangements	29.6	12.9
Net Amounts	(39.6)	0.0
Net derivative assets (liabilities)	(39.3)	34.1
Netting arrangement, gross amounts subject to master netting arrangements	0.0	0.0
Net amounts of derivative assets (liabilities)	(39.3)	34.1
Foreign exchange contracts
Derivative Asset [Abstract]
Total Gross Amounts	29.9	47.0
Gross Amounts Subject to Master Netting Arrangements	(29.6)	(12.9)
Net Amounts	0.3	34.1
Derivative Liability [Abstract]
Total Gross Amounts	(69.2)	(12.9)
Gross Amounts Subject to Master Netting Arrangements	29.6	12.9
Net Amounts	(39.6)	0.0
Designated as Cash Flow Hedges \| Cash Flow Hedging
Derivative Asset [Abstract]
Total Gross Amounts	12.0	25.0
Derivative Liability [Abstract]
Total Gross Amounts	(37.8)	(8.3)
Net derivative assets (liabilities)	(25.8)	16.7
Designated as Cash Flow Hedges \| Net Investment Hedging
Derivative Asset [Abstract]
Total Gross Amounts	0.0	0.0
Derivative Liability [Abstract]
Total Gross Amounts	(3.6)	0.0
Net derivative assets (liabilities)	(3.6)	0.0
Designated as Cash Flow Hedges \| Foreign exchange contracts \| Cash Flow Hedging
Derivative Asset [Abstract]
Total Gross Amounts	12.0	25.0
Derivative Liability [Abstract]
Total Gross Amounts	(37.8)	(8.3)
Designated as Cash Flow Hedges \| Foreign exchange contracts \| Net Investment Hedging
Derivative Asset [Abstract]
Total Gross Amounts	0.0	0.0
Derivative Liability [Abstract]
Total Gross Amounts	(3.6)	0.0
Not Designated as Hedging Instruments
Derivative Asset [Abstract]
Total Gross Amounts	17.9	22.0
Derivative Liability [Abstract]
Total Gross Amounts	(27.8)	(4.6)
Net derivative assets (liabilities)	(9.9)	17.4
Not Designated as Hedging Instruments \| Foreign exchange contracts
Derivative Asset [Abstract]
Total Gross Amounts	17.9	22.0
Derivative Liability [Abstract]
Total Gross Amounts	$ (27.8)	$ (4.6)

Derivative, Subject to Master Netting Arrangement, Offset

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The net amount as of the balance sheet date of the fair value of derivative assets and derivative liabilities that in accordance with the entity's accounting policy were offset against collateral under a master netting arrangement.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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