Railway Operating Revenues - Disaggregation of Revenues (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Disaggregation of Revenue [Line Items]
Total	$ 2,998	$ 2,993
Merchandise
Disaggregation of Revenue [Line Items]
Total	1,885	1,863
Merchandise \| Agriculture, forest and consumer products
Disaggregation of Revenue [Line Items]
Total	625	636
Merchandise \| Chemicals
Disaggregation of Revenue [Line Items]
Total	567	535
Merchandise \| Metals and construction
Disaggregation of Revenue [Line Items]
Total	413	414
Merchandise \| Automotive
Disaggregation of Revenue [Line Items]
Total	280	278
Intermodal
Disaggregation of Revenue [Line Items]
Total	749	760
Coal
Disaggregation of Revenue [Line Items]
Total	$ 364	$ 370

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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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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