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Fair Value Measurements - Narrative (Details) $ in Millions | Sep. 30, 2025 USD ($) professional
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Fair Value Disclosures [Abstract] |
AFG's internal investment professionals | professional | 20
Level 3 assets as a percentage of total assets measured at fair value | 7.00%
Percentage of internally developed level 3 assets compared to total level 3 assets | 86.00%
Internally developed level 3 assets | $ 867
Percentage of level 3 assets that were priced using a discounted cash flow approach | 67.00%
Level 3 assets that were priced using a discounted cash flow approach | $ 584
Level 3 assets that were priced using unobservable internal models and third party inputs | $ 283
Percentage of level 3 assets that were priced using financial information from third parties | 12.00%
Level 3 assets that were priced using financial information from third parties | $ 120
Percentage of level 3 assets that were priced using non-binding broker quotes or pricing services | 2.00%
Level 3 assets that were priced using non-binding broker quotes or pricing services | $ 17

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- References No definition available. + Details
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