Fair Value Disclosure - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($) Instrument	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($) Instrument
Derivative [Line Items]
Gain (loss) on cash flow hedges expected to be reclassified within next twelve months	$ 5.3
Gain (loss) on cash flow hedges expected to be reclassified within next twelve months, net of tax	4.8
Credit risk derivatives liability	11.2		$ 28.5
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Asset impairments	1.7	$ 3.6
Rail International
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Asset impairments	$ 0.0	$ 0.0
Designated as Hedging Instrument \| Fair Value Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Number of derivative instruments \| Instrument	1		1
Derivative, notional amount	$ 50.0		$ 50.0
Designated as Hedging Instrument \| Cash Flow Hedging \| Foreign Exchange Contract [Member]
Derivative [Line Items]
Number of derivative instruments \| Instrument	15		3
Derivative, notional amount	$ 1,763.0		$ 2,370.6

Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months, Gross

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Fair value of credit risk derivative asset after deduction of credit risk derivative liability.

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

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