Fair Value Measurements - Valuation of Company's Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Assets
Money market funds	$ 27,464	$ 55,473
Assets Fair Value Total	195,936	220,733
Liabilities
Total liabilities	499	936
Foreign Currency Forward Position [Member]
Liabilities
Foreign currency forward position	499	936
Mutual Funds Held In Rabbi Trust [Member]
Assets
Mutual funds held in rabbi trust	11,221	11,107
U.S. Treasuries [Member]
Assets
Trading securities	100,503	99,045
Corporate Debt [Member]
Assets
Securities available-for-sale	56,748	55,108
Level 1 [Member]
Assets
Money market funds	27,464	55,473
Assets Fair Value Total	27,464	55,473
Level 2 [Member]
Assets
Assets Fair Value Total	168,472	165,260
Liabilities
Total liabilities	499	936
Level 2 [Member] \| Foreign Currency Forward Position [Member]
Liabilities
Foreign currency forward position	499	936
Level 2 [Member] \| Mutual Funds Held In Rabbi Trust [Member]
Assets
Mutual funds held in rabbi trust	11,221	11,107
Level 2 [Member] \| U.S. Treasuries [Member]
Assets
Trading securities	100,503	99,045
Level 2 [Member] \| Corporate Debt [Member]
Assets
Securities available-for-sale	$ 56,748	$ 55,108

Money market funds fair value.

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Fair value portion of asset recognized for present right to economic benefit.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value of financial and nonfinancial obligations.

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