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Commitments and Contingencies - Schedule of Personal Injury Liability Activity (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Loss Contingency Accrual [Roll Forward] |  |  |
Current portion, ending balance at September 30, | $ 307 |  | $ 319
Personal Injury |  |  |
Loss Contingency Accrual [Roll Forward] |  |  |
Beginning balance | 379 | $ 383 |
Current year accruals | 82 | 87 |
Changes in estimates for prior years | 9 | (2) |
Payments | (81) | (75) |
Ending balance at September 30, | 389 | 393 |
Current portion, ending balance at September 30, | $ 105 | $ 114 |

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- Definition Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-1 + Details
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- Definition Amount of cash outflow reducing loss contingency liability. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-1 + Details
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- Definition Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-1 + Details
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