Segment Reporting - Schedule of Cost and Expense (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
Sep. 30, 2026 |
Jun. 30, 2026 |
Mar. 31, 2026 |
Sep. 30, 2025 |
Jun. 30, 2025 |
Mar. 31, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Segment Reporting [Line Items] | ||||||||
| Railway operating revenues | $ 3,526 | $ 3,103 | $ 9,989 | $ 9,206 | ||||
| Railway operating expenses | ||||||||
| Compensation and benefits | 753 | 738 | 2,237 | 2,169 | ||||
| Fuel | 420 | 237 | 1,081 | 700 | ||||
| Depreciation | 363 | 348 | 1,073 | 1,040 | ||||
| Merger-related expenses | 42 | 15 | 145 | 15 | ||||
| Restructuring and other charges | 0 | 12 | 6 | 22 | ||||
| Eastern Ohio incident | 28 | 53 | ||||||
| Eastern Ohio incident | (11) | (243) | ||||||
| Total railway operating expenses | 2,376 | 2,005 | 6,838 | 5,787 | ||||
| Income from railway operations | 1,150 | 1,098 | 3,151 | 3,419 | ||||
| Other income – net | 30 | 23 | 97 | 78 | ||||
| Interest expense on debt | 193 | 197 | 587 | 597 | ||||
| Income before income taxes | 987 | 924 | 2,661 | 2,900 | ||||
| Income taxes | 228 | 213 | 621 | 671 | ||||
| Net income | 759 | $ 734 | $ 547 | 711 | $ 768 | $ 750 | 2,040 | 2,229 |
| Reportable Segment | ||||||||
| Segment Reporting [Line Items] | ||||||||
| Railway operating revenues | 3,526 | 3,103 | 9,989 | 9,206 | ||||
| Railway operating expenses | ||||||||
| Compensation and benefits | 753 | 738 | 2,237 | 2,169 | ||||
| Purchased services | 433 | 414 | 1,286 | 1,224 | ||||
| Equipment rents | 113 | 105 | 332 | 313 | ||||
| Fuel | 420 | 237 | 1,081 | 700 | ||||
| Depreciation | 363 | 348 | 1,073 | 1,040 | ||||
| Materials | 111 | 104 | 318 | 302 | ||||
| Claims | 87 | 75 | 209 | 200 | ||||
| Other | 26 | (32) | 98 | 45 | ||||
| Merger-related expenses | 42 | 15 | 145 | 15 | ||||
| Restructuring and other charges | 0 | 12 | 6 | 22 | ||||
| Eastern Ohio incident | 28 | 53 | ||||||
| Eastern Ohio incident | (11) | (243) | ||||||
| Total railway operating expenses | 2,376 | 2,005 | 6,838 | 5,787 | ||||
| Income from railway operations | 1,150 | 1,098 | 3,151 | 3,419 | ||||
| Other income – net | 30 | 23 | 97 | 78 | ||||
| Interest expense on debt | 193 | 197 | 587 | 597 | ||||
| Income before income taxes | 987 | 924 | 2,661 | 2,900 | ||||
| Income taxes | 228 | 213 | 621 | 671 | ||||
| Net income | $ 759 | $ 711 | $ 2,040 | $ 2,229 | ||||
| X | ||||||||||
- Definition Equipment rents No definition available.
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- Definition Purchased Services No definition available.
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- Definition Restructuring And Other Charges No definition available.
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- Definition Amount of expense for acquisition-related cost incurred to effect business combination. Includes, but is not limited to, finder's fee; advisory, legal, accounting, valuation, and other professional and consulting fees; and general administrative cost, including cost of maintaining internal acquisition department. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Cost of material used for good produced and service rendered. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Total costs of sales and operating expenses for the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fuel costs incurred that are directly related to goods produced and sold and services rendered during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of interest expense classified as nonoperating. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition The net result for the period of deducting operating expenses from operating revenues. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Insurance and claims costs directly related to goods produced and sold, or services rendered, during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of income (expense) related to nonoperating activities, classified as other. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations. No definition available.
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of gain recognized in the income statement for an event or transaction that is unusual in nature or infrequent in occurrence, or both. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before deduction of insurance proceeds, of loss recognized in the income statement for an event or transaction that is unusual in nature or infrequent in occurrence, or both. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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