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Fair Value Measurements - Narrative (Details) $ in Millions | Mar. 31, 2024 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 | 8.00%
Percentage of level 3 assets that were priced using non-binding broker quotes | 8.00%
Level 3 assets that were priced using non-binding broker quotes | $ 109
Percentage of level 3 assets that were priced by pricing services | 1.00%
Level 3 assets that were priced by pricing services. | $ 10
Percentage of level 3 equity investments that do not qualify for equity accounting | 31.00%
Level 3 assets that are equity securities that do not qualify for equity accounting | $ 397
Percentage of internally developed level 3 assets compared to total level 3 assets | 60.00%
Internally developed level 3 assets | $ 781
Percentage of level three assets that were priced using a discounted cash flow approach | 73.00%
Level three assets that were priced using a discounted cash flow approach | $ 566
Percentage of level three assets, equity securities, priced using broker quotes and internal models | 18.00%
Level three assets, equity securities, priced using broker quotes and internal models | $ 144

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