Fair Value Measurements - Valuation of Company's Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Assets
Money market funds	$ 18,571	$ 18,634
Assets Fair Value Total	154,402	155,396
Liabilities
Total liabilities	196
Foreign Currency Forward Position [Member]
Assets
Foreign currency forward position		1,901
Liabilities
Foreign currency forward position	196
Mutual Funds Held In Rabbi Trust [Member]
Assets
Trading securities	11,015	10,485
Mutual funds held in rabbi trust	11,015	10,485
U.S. Treasuries [Member]
Assets
Trading securities	99,427	99,682
Corporate Debt [Member]
Assets
Securities available-for-sale	25,389	24,694
Trading securities	25,389	24,694
Level 1 [Member]
Assets
Money market funds	18,571	18,634
Assets Fair Value Total	18,571	18,634
Level 2 [Member]
Assets
Assets Fair Value Total	135,831	136,762
Liabilities
Total liabilities	196
Level 2 [Member] \| Foreign Currency Forward Position [Member]
Assets
Foreign currency forward position		1,901
Liabilities
Foreign currency forward position	196
Level 2 [Member] \| Mutual Funds Held In Rabbi Trust [Member]
Assets
Mutual funds held in rabbi trust	11,015	10,485
Level 2 [Member] \| U.S. Treasuries [Member]
Assets
Trading securities	99,427	99,682
Level 2 [Member] \| Corporate Debt [Member]
Assets
Securities available-for-sale	$ 25,389	$ 24,694

Money market funds fair value.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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 liability, of financial asset or other 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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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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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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