CONDENSED CONSOLIDATED STATEMENT OF COMPREHENSIVE (LOSS) INCOME - 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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| Statement of Comprehensive Income [Abstract] | ||||
| Net (Loss) Income Attributable to Merck & Co., Inc. | $ (1,335) | $ 4,427 | $ (5,575) | $ 9,506 |
| Other Comprehensive Income (Loss) Net of Taxes: | ||||
| Net unrealized gain (loss) on derivatives, net of reclassifications | 75 | (410) | 291 | (627) |
| Benefit plan net gain (loss) and prior service credit (cost), net of amortization | 8 | (8) | 13 | (26) |
| Cumulative translation adjustment | 35 | (38) | 41 | 177 |
| Other comprehensive income (loss), net of taxes | 118 | (456) | 345 | (476) |
| Comprehensive (Loss) Income Attributable to Merck & Co., Inc. | $ (1,217) | $ 3,971 | $ (5,230) | $ 9,030 |
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- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness, attributable to parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount after tax of other comprehensive income (loss) attributable to parent entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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