Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Statement of Comprehensive Income [Abstract] | ||||
| Net income | $ 486 | $ 470 | $ 2,290 | $ 2,046 |
| Less: Net income attributable to redeemable and nonredeemable noncontrolling interests | 10 | 12 | 51 | 44 |
| Net income attributable to Aon shareholders | 476 | 458 | 2,239 | 2,002 |
| Other comprehensive income (loss), net of tax: | ||||
| Change in fair value of financial instruments | 26 | (9) | 17 | 4 |
| Foreign currency translation adjustments | 29 | (91) | (157) | 752 |
| Postretirement benefit obligation | 26 | 28 | 78 | 74 |
| Total other comprehensive income (loss) | 81 | (72) | (62) | 830 |
| Less: Other comprehensive income attributable to noncontrolling interests | 0 | 0 | 0 | 0 |
| Total other comprehensive income (loss) attributable to Aon shareholders | 81 | (72) | (62) | 830 |
| Comprehensive income attributable to Aon shareholders | $ 557 | $ 386 | $ 2,177 | $ 2,832 |
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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 of Net Income (Loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax and reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount after tax of other comprehensive income (loss) attributable to noncontrolling interests. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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- Definition Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after tax and before adjustment, of unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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