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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 portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value of financial and nonfinancial obligations.

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Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Nov. 13, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	$ 338,836	$ 610,840
Contingent consideration			$ 24,000
U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	77,789	258,304
Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	189,620	254,413
Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	56,901	83,615
Certificates of Deposit and Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	1,356	979
U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	4,610	4,339
Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	7,971	8,565
Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	589	625
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	1,500,288	1,554,381
Derivative assets	92	95
Total	1,500,380	1,554,476
Contingent consideration		7,227
Derivative liabilities	118	504
Total	118	7,731
Fair Value, Measurements, Recurring \| Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	628,740	443,166
Fair Value, Measurements, Recurring \| Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	493,459	470,955
Fair Value, Measurements, Recurring \| U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	77,789	258,304
Fair Value, Measurements, Recurring \| Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	189,620	254,413
Fair Value, Measurements, Recurring \| Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	56,901	83,615
Fair Value, Measurements, Recurring \| Certificates of Deposit and Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	1,356	979
Fair Value, Measurements, Recurring \| U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	4,610	4,339
Fair Value, Measurements, Recurring \| Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	7,971	8,565
Fair Value, Measurements, Recurring \| Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	589	625
Fair Value, Measurements, Recurring \| Equity Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale equity securities	39,253	29,420
Quoted Prices in Active Markets for Identical Instruments (Level 1) \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	1,088,176	828,919
Total	1,088,176	828,919
Quoted Prices in Active Markets for Identical Instruments (Level 1) \| Fair Value, Measurements, Recurring \| Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	628,740	443,166
Quoted Prices in Active Markets for Identical Instruments (Level 1) \| Fair Value, Measurements, Recurring \| Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	412,212	347,768
Quoted Prices in Active Markets for Identical Instruments (Level 1) \| Fair Value, Measurements, Recurring \| Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	7,971	8,565
Quoted Prices in Active Markets for Identical Instruments (Level 1) \| Fair Value, Measurements, Recurring \| Equity Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale equity securities	39,253	29,420
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	412,112	725,462
Derivative assets	92	95
Total	412,204	725,557
Derivative liabilities	118	504
Total	118	504
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	81,247	123,187
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	77,789	258,304
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	189,620	254,413
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	56,901	83,615
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Certificates of Deposit and Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	1,356	979
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	4,610	4,339
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	589	625
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Contingent consideration		7,227
Total	$ 0	$ 7,227