Fair Value Measurements - Schedule Of Fair Value Measurements, By Major Security Type (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 446,243	$ 427,288
Fair Value Measurements on Recurring Basis
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	446,243	427,288
Cash equivalents and short-term investments	475,488	507,183
Fair Value Measurements on Recurring Basis | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	167,939	134,833
Cash equivalents and short-term investments	197,184	214,728
Fair Value Measurements on Recurring Basis | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	278,304	292,455
Cash equivalents and short-term investments	278,304	292,455
Fair Value Measurements on Recurring Basis | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	29,245	79,895
Fair Value Measurements on Recurring Basis | Money Market Funds | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	29,245	79,895
Fair Value Measurements on Recurring Basis | Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	188,699	207,172
Fair Value Measurements on Recurring Basis | Corporate Debt Securities | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	188,699	207,172
Fair Value Measurements on Recurring Basis | U.S. Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	167,939	134,833
Fair Value Measurements on Recurring Basis | U.S. Treasury Securities | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	167,939	134,833
Fair Value Measurements on Recurring Basis | Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	58,427	53,439
Fair Value Measurements on Recurring Basis | Commercial Paper | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	58,427	53,439
Fair Value Measurements on Recurring Basis | Non U S Government And Supranational Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	22,375	22,908
Fair Value Measurements on Recurring Basis | Non U S Government And Supranational Debt Securities | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	22,375	22,908
Fair Value Measurements on Recurring Basis | U S Agency Bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	8,803	8,936
Fair Value Measurements on Recurring Basis | U S Agency Bonds | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 8,803	$ 8,936