Summary of Calculation of Realized Gains and Losses (Detail) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Investments, Debt and Equity Securities [Abstract] | ||||
| Net realized gains (losses) | $ 244 | $ 161 | $ (2,020) | $ 284 |
| Less: net gains (losses) recognized during the period on equity securities sold during the period | 0 | 0 | (1,075) | 0 |
| Unrealized gains (losses) recognized during the reporting period on equity securities still held | $ 244 | $ 161 | $ (945) | $ 284 |