Summary of Calculation of Realized Gains and Losses (Detail) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Investments, Debt and Equity Securities [Abstract] | ||
| Net realized gains (losses) | $ (2,264) | $ 123 |
| Less: net gains (losses) recognized during the period on equity securities sold during the period | (1,075) | 0 |
| Unrealized gains (losses) recognized during the reporting period on equity securities still held | $ (1,189) | $ 123 |