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v3.24.2

Investments - Additional Information (Detail) $ in Thousands | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2024 USD ($) Security | Jun. 30, 2023 USD ($) | Jun. 30, 2024 USD ($) Security | Jun. 30, 2023 USD ($) | Mar. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Marketable Securities [Line Items] |  |  |  |  |  |
Individual fixed maturity held in unrealized loss position | Security | 170 |  | 170 |  |  |
Number of fixed maturity securities, allowance for credit loss | Security | 450 |  | 450 |  |  |
Fixed maturity securities, held-to-maturity, allowance for credit losses | $ 149 |  | $ 149 |  | $ 165 | $ 182
Available-for-sale, Allowance for Credit Losses | 0 |  | 0 |  |  | 0
Net realized gains (losses) on investments | (117) | $ 75 | (339) | $ 333 |  |
Net unrealized gains (losses) on equity securities | (58) | $ 2,048 | 4,718 | $ 3,417 |  |
Corporate Bonds [Member] |  |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |  |
Fixed maturity securities, held-to-maturity, allowance for credit losses | $ 111 |  | $ 111 |  | 126 | 142
Number of majority securities | Security | 19 |  | 19 |  |  |
States and Political Subdivisions [Member] |  |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |  |
Fixed maturity securities, held-to-maturity, allowance for credit losses | $ 36 |  | $ 36 |  | $ 37 | $ 38
Number of majority securities | Security | 428 |  | 428 |  |  |
Corporate Fixed Income Securities [Member] | Maximum [Member] |  |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |  |
Investments maturity period using default rate |  |  | 20 years |  |  |

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