Employee Benefit Plans (Amounts Recognized in the Balance Sheet) (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
| Current pension and PRB liabilities (included in Accrued employee compensation) | $ 227 | $ 228 |
| Future pension and postretirement benefit obligations | 1,913 | 2,067 |
| Pension | ||
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
| Non-current pension assets (included in Other assets) | 3,216 | 2,339 |
| Future pension and postretirement benefit obligations | 1,389 | 1,510 |
| PRB | ||
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
| Future pension and postretirement benefit obligations | 454 | 501 |
| Other pension and PRB related items | ||
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
| Future pension and postretirement benefit obligations | $ 70 | $ 56 |
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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. No definition available.
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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