Pension plans - Additional tabular disclosures (Detail) - Pension Plans, Defined Benefit [Member] - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Discount rate applicable to PBOs | 5.40% | 5.50% | 5.00% |
| Expected long-term rate of return on plan assets | 6.30% | 5.90% | 6.00% |
| Rate of compensation increase, if applicable | 2.60% | 2.60% | 2.60% |
| Discount rate applicable to net periodic pension expense | 5.50% | 5.10% | 5.30% |
| Amounts recognized in other comprehensive income: | |||
| Accumulated other comprehensive income (loss), beginning of the year | $ 1,467 | $ (161) | |
| Amount included in net periodic pension expense | (68) | 29 | |
| Actuarial gains (losses) and other | (732) | 1,599 | |
| Accumulated other comprehensive income (loss), end of the year | $ 667 | $ 1,467 | $ (161) |
| X | ||||||||||
- Definition An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested. No definition available.
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- Definition Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. 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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| X | ||||||||||
- Definition Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for net period benefit cost (credit) of defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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