Investments - Summary of Details on Realized and Unrealized Gains and Losses Related to Equity Securities (Detail) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2022 |
Sep. 30, 2021 |
Sep. 30, 2022 |
Sep. 30, 2021 |
|
| Investments, Debt and Equity Securities [Abstract] | ||||
| Unrealized gains (losses) recognized during the reported period on equity securities still held at the end of the reported period | $ (4,150) | $ (3,418) | $ (16,387) | $ (2,391) |