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Components of Net Realized Investment Gains (Losses) (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Schedule Of Available For Sale Securities [Line Items] |  |  |  |
Total net realized investment gains (losses) | $ (512) | $ (133) | $ 540 | $ (2,414)
Equity securities, Gross realized gains | 295 | 163 | 1,384 | 726
Equity securities, Gross realized losses | (6) | (178) | (11) | (1,829)
Equity securities, Total net realized investment gains (losses) | 289 | (15) | 1,373 | (1,103)
Fixed Income Securities |  |  |  |
Schedule Of Available For Sale Securities [Line Items] |  |  |  |
Gross realized gains | 5 | 15 | 54 | 29
Gross realized losses | (806) | (133) | (887) | (1,340)
Total net realized investment gains (losses) | $ (801) | $ (118) | $ (833) | $ (1,311)

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