Accounting Policies and Interim Results (Details) - Burlington Northern Santa Fe Corporation	Sep. 30, 2025	Feb. 12, 2010
Business Combination [Line Items]
Acquired remaining outstanding shares, percentage		100.00%
Holders of membership interests	1

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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