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Fair Value Measurements - Narrative (Details) $ in Millions | Mar. 31, 2026 USD ($) professional
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Fair Value Disclosures [Abstract] |
AFG's internal investment professionals | professional | 25
Level 3 assets as a percentage of total assets measured at fair value | 6.00%
Percentage of internally developed level 3 assets compared to total level 3 assets | 88.00%
Internally developed level 3 assets | $ 894
Percentage of level 3 assets that were priced using a discounted cash flow approach | 68.00%
Level 3 assets that were priced using a discounted cash flow approach | $ 612
Level 3 assets that were priced using unobservable internal models and third party inputs | $ 282
Percentage of level 3 assets that were priced using financial information from third parties | 9.00%
Level 3 assets that were priced using financial information from third parties | $ 92
Percentage of level 3 assets that were priced using non-binding broker quotes or pricing services | 3.00%
Level 3 assets that were priced using non-binding broker quotes or pricing services | $ 29

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- References No definition available. + Details
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