Commitments and Contingencies Insurance (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Loss Contingencies [Line Items]
Cash and cash equivalents	$ 2,441	$ 2,463
Commercial Paper, Bank Time Deposits, and Money Market Funds \| BNSF Insurance Company
Loss Contingencies [Line Items]
Cash and cash equivalents	$ 603	$ 593

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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+ Details