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Fair Value Measurements - Summary of Company's Investments (Detail) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Schedule Of Available For Sale Securities [Line Items] |  |
Investments, Amortized cost | $ 166,967 | $ 166,143
Investments, Gross unrealized gains | 1,538 | 1,074
Investments, Gross unrealized losses | (33) | (1,957)
Investments, Fair value | 168,472 | 165,260
Corporate Debt [Member] |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Securities available-for-sale, Amortized Cost | 56,460 | 55,447
Securities available-for-sale, Gross unrealized gains | 300 | 88
Securities available-for-sale, Gross unrealized losses | (12) | (427)
Securities available-for-sale, Fair value | 56,748 | 55,108
U.S. Treasuries [Member] |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Trading securities, Amortized cost | 100,270 | 100,484
Trading securities, Gross unrealized gains | 254 | 86
Trading securities, Gross unrealized losses | (21) | (1,525)
Trading securities, Fair value | 100,503 | 99,045
Mutual Funds Held In Rabbi Trust [Member] |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Trading securities, Amortized cost | 10,237 | 10,212
Trading securities, Gross unrealized gains | 984 | 900
Trading securities, Gross unrealized losses | 0 | (5)
Trading securities, Fair value | $ 11,221 | $ 11,107

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