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Fair Value Measurements - Narrative (Details) $ in Millions | Jun. 30, 2021 USD ($) professional
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
AFG's internal investment professionals | professional | 20
Level 3 | Continuing operations |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Level 3 assets as a percentage of total assets measured at fair value | 5.00%
Percentage of level 3 assets that were priced using non-binding broker quotes | 24.00%
Level 3 assets that were priced using non-binding broker quotes | $ 206
Level three assets that were priced by pricing services. | $ 68
Percentage Of Level Three Assets That Were Priced By Pricing Services | 8.00%
Internally developed level 3 assets | $ 491
Percentage Of Internally Developed Level Three Assets Compared to Total Level 3 Assets | 57.00%

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