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Fair Value Measurement - Additional Information (Details) $ in Millions | Mar. 31, 2025 USD ($) Trust security | Dec. 31, 2024
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Total |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Percentage of CDS contracts fair valued using minimum premium | 0.00% | 0.00%
AGC |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Number of custodial trusts | Trust | 8 |
Share value, amount | $ 400 |
Maximum amount | $ 50 |
Recurring | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Number of fixed maturity securities valued using model processes | security | 175 |

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