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Fair Value Measurements - Summary of Companies Unrealized and Realized Gains and Losses on Investments (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Gain (Loss) on Securities [Line Items] |  |  |
Unrealized gains/(losses) | $ 2,409 | $ 19 | $ 1,719
Realized gains/(losses) | 1,264 | (324) | (149)
Securities sold, not yet purchased gross realized gains | 0 | 174 | 0
Corporate Debt [Member] |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Unrealized gains/(losses) | 669 | (328) | (11)
Realized gains/(losses) | 5 | 4 | (11)
U.S. Treasuries [Member] |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Unrealized gains/(losses) | 1,733 | (1,025) | 446
Mutual Funds Held In Rabbi Trust [Member] |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Unrealized gains/(losses) | 7 | 1,372 | 1,284
Realized gains/(losses) | $ 1,259 | $ (328) | $ (138)

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