ADDITIONAL FINANCIAL INFORMATION (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |
1 Months Ended | 3 Months Ended | 4 Months Ended | |||
|---|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Organization, Consolidation and Presentation of Financial Statements [Abstract] | ||||||
| Revenue | $ 839 | $ 745 | $ 2,442 | $ 2,259 | $ 3,281 | $ 3,004 |
| Operating expenses: | ||||||
| Salaries and employee benefits | 378 | 349 | 1,128 | 1,084 | 1,506 | 1,433 |
| Operating supplies and expenses | 176 | 150 | 546 | 471 | 722 | 621 |
| Purchased transportation | 74 | 65 | 235 | 200 | 309 | 265 |
| Depreciation and amortization | 38 | 43 | 114 | 125 | 152 | 168 |
| Insurance and claims | 15 | 14 | 44 | 42 | 59 | 56 |
| Operating taxes and licenses | 6 | 6 | 17 | 17 | 23 | 23 |
| Separation and other costs | 22 | 0 | 105 | 30 | 127 | 30 |
| Total operating expenses | 709 | 627 | 2,189 | 1,969 | 2,898 | 2,596 |
| Operating income | 130 | 118 | 253 | 290 | 383 | 408 |
| Other income (expense): | ||||||
| Related party interest income | 0 | 30 | ||||
| Interest, net | (18) | 0 | ||||
| Other, net | 2 | 2 | 1 | 3 | 3 | 5 |
| Total other income (expense) | (16) | 32 | (49) | 101 | (65) | 133 |
| Income before income taxes | 114 | 150 | 204 | 391 | 318 | 541 |
| Provision for income taxes | 31 | 37 | 57 | 100 | 88 | 137 |
| Net income | $ 83 | $ 113 | $ 147 | $ 291 | $ 230 | $ 404 |
| Earnings per share: | ||||||
| Basic (in dollar per share) | $ 0.56 | $ 0.76 | $ 0.98 | $ 1.95 | $ 1.54 | $ 2.70 |
| Diluted (in dollar per share) | $ 0.56 | $ 0.76 | $ 0.98 | $ 1.95 | $ 1.54 | $ 2.70 |
| Weighted-average shares outstanding: | ||||||
| Basic (in shares) | 149.5 | 149.5 | 149.5 | 149.5 | 149.5 | 149.5 |
| Diluted (in shares) | 149.9 | 149.5 | 149.9 | 149.5 | 149.9 | 149.5 |
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- Definition Purchased Transportation Costs No definition available.
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- Definition Separation And Other Costs No definition available.
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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 aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The expense in the period incurred with respect to protection provided by insurance entities against risks other than risks associated with production (which are allocated to cost of sales). 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 income (expense) classified as nonoperating. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities. 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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- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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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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- References No definition available.
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- Definition The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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 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 Amount of tax expense, excluding income, excise, production and property taxes, and licenses and fees not related to production. No definition available.
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- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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