Income taxes - Reconciliation of unrecognized tax benefits (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Reconciliation of the beginning and ending amount of gross unrecognized tax benefits | |||
| Beginning balance | $ 1,289 | $ 1,223 | $ 1,140 |
| Additions for tax positions related to current year | 68 | 118 | 94 |
| Additions for tax positions related to prior years | 35 | 49 | 42 |
| Reductions for tax positions related to prior years | (6) | (30) | (19) |
| Reductions for settlements | (29) | (60) | (27) |
| Reductions for expiration of statute of limitations | (10) | (11) | (7) |
| Ending balance | 1,347 | 1,289 | 1,223 |
| Amount that, if recognized, would impact the effective tax rate | $ 1,199 | $ 1,137 | $ 997 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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