Employee Benefit Plans (Components of Provision for Net Periodic Benefit (Credit) Cost) (Detail) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Pension Benefits | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | $ 19 | $ 19 | $ 38 | $ 38 |
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Nonoperating Income (Expense) | Other Nonoperating Income (Expense) | Other Nonoperating Income (Expense) | Other Nonoperating Income (Expense) |
| Interest cost | $ 107 | $ 109 | $ 215 | $ 217 |
| Expected return on plan assets | (158) | (169) | (317) | (338) |
| Amortization of prior service cost (credit) | 1 | 0 | 1 | 0 |
| Net periodic benefit (credit) cost | (31) | (41) | (63) | (83) |
| Other Postretirement Benefits | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | $ 3 | $ 2 | $ 5 | $ 5 |
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Nonoperating Income (Expense) | Other Nonoperating Income (Expense) | Other Nonoperating Income (Expense) | Other Nonoperating Income (Expense) |
| Interest cost | $ 14 | $ 15 | $ 27 | $ 29 |
| Expected return on plan assets | (44) | (40) | (87) | (80) |
| Amortization of prior service cost (credit) | (6) | (7) | (11) | (13) |
| Net periodic benefit (credit) cost | $ (33) | $ (30) | $ (66) | $ (59) |
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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 expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Indicates line item in statement of income or comprehensive income that includes components of net periodic benefit cost (credit), excluding service cost component, for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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