Guarantees (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Guarantor Obligations [Line Items]
Environmental accruals for known contaminations	$ 467	$ 506
Secured Debt \| Receivables Securitization Facility due September 2025 at 5.182% at year-end 2024
Guarantor Obligations [Line Items]
Maximum potential amount of future payments under the guarantees	295
Secured Debt \| Receivables Securitization Facility due September 2025 at 5.182% at year-end 2024 \| Line of Credit
Guarantor Obligations [Line Items]
Line of credit facility, utilized	346	367
Joint Venture Debt Obligation Guarantees \| Other joint ventures and entities
Guarantor Obligations [Line Items]
Maximum potential amount of future payments under the guarantees	$ 52
Joint venture debt obligations, period (up to)	3 years
Indemnifications
Guarantor Obligations [Line Items]
Carrying amount of indemnifications	$ 52	53
Environmental accruals for known contaminations	49	$ 50
Facilities \| Residual Value Guarantees
Guarantor Obligations [Line Items]
Maximum potential amount of future payments under the guarantees	404
Railcar and Airplane \| Residual Value Guarantees
Guarantor Obligations [Line Items]
Maximum potential amount of future payments under the guarantees	$ 174
Railcar and Airplane \| Residual Value Guarantees \| Minimum
Guarantor Obligations [Line Items]
Lessee operating lease remaining lease term (up to)	1 year
Railcar and Airplane \| Residual Value Guarantees \| Maximum
Guarantor Obligations [Line Items]
Lessee operating lease remaining lease term (up to)	10 years

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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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.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Maximum month-end amount borrowed under the credit facility during the period.

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