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Fair Value Measurements - Information about Valuation Inputs for Fixed Income Securities Classified as Level 3 (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2024
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Other Investments | $ 18,317 | $ 28,294
Debt Securities, Available-for-sale | 135,224 | 157,020
Residential Mortgage-Backed Securities [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Debt Securities, Available-for-sale | 0 | 2,446
Corporate Obligations [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Debt Securities, Available-for-sale | 87,991 | 89,192
Fair Value, Recurring [Member] | Residential Mortgage-Backed Securities [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Debt Securities, Available-for-sale | 0 | 2,446
Fair Value, Recurring [Member] | Residential Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Debt Securities, Available-for-sale | 0 | 0
Fair Value, Recurring [Member] | Corporate Obligations [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Debt Securities, Available-for-sale | 87,991 | 89,192
Fair Value, Recurring [Member] | Corporate Obligations [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Debt Securities, Available-for-sale | $ 13,920 | $ 0
Fair Value Inputs Maturity | 9 months |

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