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Fair Value Measurements - Fair Values of Financial Assets Measured on Recurring Basis (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
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Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | $ 130,426 | $ 270,656
Corporate bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 11,910 | 82,008
Commercial paper [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 55,858 | 57,381
Asset-backed securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 2,474
Foreign government bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 4,980
Convertible promissory note [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 1,000
Fair Value, Measurements, Recurring [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total fair value of financial assets | 180,358 | 290,537
Fair Value, Measurements, Recurring [Member] | Money market funds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets fair value disclosure | 22,016 | 19,881
Fair Value, Measurements, Recurring [Member] | Corporate bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 11,910 | 82,008
Fair Value, Measurements, Recurring [Member] | Commercial paper [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 78,800 | 57,381
Fair Value, Measurements, Recurring [Member] | U.S. government bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 62,665 | 111,345
Fair Value, Measurements, Recurring [Member] | Agency bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 4,967 | 11,468
Fair Value, Measurements, Recurring [Member] | Asset-backed securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 2,474
Fair Value, Measurements, Recurring [Member] | Foreign government bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 4,980
Fair Value, Measurements, Recurring [Member] | Convertible promissory note [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 1,000
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total fair value of financial assets | 40,850 | 118,853
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Money market funds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets fair value disclosure | 22,016 | 19,881
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Corporate bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Commercial paper [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | U.S. government bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 18,834 | 98,972
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Agency bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Asset-backed securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Foreign government bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Convertible promissory note [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total fair value of financial assets | 139,508 | 170,684
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Money market funds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets fair value disclosure | 0 | 0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Corporate bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 11,910 | 82,008
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Commercial paper [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 78,800 | 57,381
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | U.S. government bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 43,831 | 12,373
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Agency bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 4,967 | 11,468
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Asset-backed securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 2,474
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Foreign government bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 4,980
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Convertible promissory note [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Total fair value of financial assets | 0 | 1,000
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Money market funds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets fair value disclosure | 0 | 0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Corporate bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Commercial paper [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | U.S. government bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | 0 | 0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Agency bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments | $ 0 | 0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Asset-backed securities [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Foreign government bonds [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | 0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Convertible promissory note [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Investments |  | $ 1,000

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (aa) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + Details
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- Definition 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. + References No definition available. + Details
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