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Summary of Estimated Fair Values of Bonds Held on Deposit (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Schedule Of Available For Sale Securities [Line Items] |  |  |
Estimated Fair Value | [1] | $ 184,351 | $ 178,342
On Deposit With Governmental Authorities |  |  |
Schedule Of Available For Sale Securities [Line Items] |  |  |
Estimated Fair Value |  | 19,861 | 19,378
Held In Trust Pursuant To Third Party Requirements |  |  |
Schedule Of Available For Sale Securities [Line Items] |  |  |
Estimated Fair Value |  | $ 164,490 | $ 158,964
[1] | Includes cash and cash equivalents of $25.3 million and $5.2 million at September 30, 2025 and December 31, 2024, respectively, with the remainder related to bonds available for sale.

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