Realized and Net Change in Unrealized Gains (Losses) on Investments (Detail) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Gain (Loss) on Securities [Line Items] | ||||
| Total realized and net change in unrealized gains (losses) | $ 2,472,721 | $ 1,605,665 | $ 3,617,364 | $ 2,775,171 |
| Corporate Treasury Investments | ||||
| Gain (Loss) on Securities [Line Items] | ||||
| Realized Gains (Losses) | (47) | 171 | 1,232 | (8,185) |
| Net Change in Unrealized Gains (Losses) | 17,975 | 11,497 | (816) | 14,546 |
| Total realized and net change in unrealized gains (losses) | $ 17,928 | $ 11,668 | $ 416 | $ 6,361 |