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Insurance - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Insurance [Line Items] |  |  |
Carrying value of cash and securities owned by U.S.-based insurance subsidiaries on deposit | $ 1,220 |  |
Workers' compensation insurance discount rate | 4.50% | 3.50% |
Amortization of deferred policy acquisition costs | $ 720 | $ 641 | $ 580
Dividends on common stock | 687 | 1,220 | $ 2,380
Dividends payments without violating the most restrictive debt covenants, minimum | 1,500 |  |
Maximum |  |  |
Insurance [Line Items] |  |  |
Maximum amount of dividends available to be paid by insurance subsidiaries to AFG without prior approval of regulatory authorities | $ 944 |  |
Catastrophe Bonds |  |  |
Insurance [Line Items] |  |  |
Catastrophe reinsurance coverage, excess retention percentage | 94.00% |  |
Reinsurance, excess retention, amount reinsured, per event | $ 323 |  |
Reinsurance, amount retained, per event | 127 |  |
Catastrophe reinsurance coverage, annual cost | 16 |  |
Workers' Compensation Insurance |  |  |
Insurance [Line Items] |  |  |
Impact of discount on workers' compensation policies | $ 9 |  |
Impact of discount on workers' compensation policies, prior year amount |  | $ 9 |

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