Fair Value Measurements - Valuation of Company's Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets
Money market funds	$ 14,206	$ 20,856
Assets Fair Value Total	50,284	48,967
Liabilities
Contingent consideration payable	41,090	15,026
Total liabilities		15,831
Corporate Debt [Member]
Assets
Trading securities		19,222
Mutual Funds Held In Rabbi Trust [Member]
Assets
Trading securities	11,195	8,889
Foreign Currency Forward Position [Member]
Liabilities
Foreign currency forward position		805
U.S. Treasuries [Member]
Assets
Trading securities	24,883
Level 1 [Member]
Assets
Money market funds	14,206	20,856
Assets Fair Value Total	14,206	20,856
Level 2 [Member]
Assets
Assets Fair Value Total	36,078	28,111
Liabilities
Total liabilities		805
Level 2 [Member] \| Corporate Debt [Member]
Assets
Trading securities		19,222
Level 2 [Member] \| Mutual Funds Held In Rabbi Trust [Member]
Assets
Trading securities	11,195	8,889
Level 2 [Member] \| Foreign Currency Forward Position [Member]
Liabilities
Foreign currency forward position		805
Level 2 [Member] \| U.S. Treasuries [Member]
Assets
Trading securities	24,883
Level 3 [Member]
Liabilities
Contingent consideration payable	$ 41,090	15,026
Total liabilities		$ 15,026

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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 liability recognized arising from contingent consideration in a business combination.

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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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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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