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Fair Value Measurement - Schedule of Financial Instruments Recorded at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Fair Value (Recurring) [Line Items] |  |
Fair Value | $ 202,935 | $ 301,125
U.S. Treasury securities |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 159,050 | 219,104
U.S. Agency securities |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 29,330 | 19,264
Certificates of deposit |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 3,365 | 26,509
Corporate debt securities |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 1,684 | 13,848
Commercial paper |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 9,506 | 22,400
Fair Value Measurements Recurring |  |
Fair Value (Recurring) [Line Items] |  |
Cash equivalents - money market mutual funds | 8,842 | 5,608
Total cash equivalents and marketable securities | 211,777 | 306,733
Fair Value Measurements Recurring | Level 1 |  |
Fair Value (Recurring) [Line Items] |  |
Cash equivalents - money market mutual funds | 8,842 | 5,608
Total cash equivalents and marketable securities | 8,842 | 5,608
Fair Value Measurements Recurring | Level 2 |  |
Fair Value (Recurring) [Line Items] |  |
Cash equivalents - money market mutual funds | 0 | 0
Total cash equivalents and marketable securities | 202,935 | 301,125
Fair Value Measurements Recurring | Level 3 |  |
Fair Value (Recurring) [Line Items] |  |
Cash equivalents - money market mutual funds | 0 | 0
Total cash equivalents and marketable securities | 0 | 0
Fair Value Measurements Recurring | U.S. Treasury securities |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 159,050 | 219,104
Fair Value Measurements Recurring | U.S. Treasury securities | Level 1 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 0 | 0
Fair Value Measurements Recurring | U.S. Treasury securities | Level 2 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 159,050 | 219,104
Fair Value Measurements Recurring | U.S. Treasury securities | Level 3 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 0 | 0
Fair Value Measurements Recurring | U.S. Agency securities |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 29,330 | 19,264
Fair Value Measurements Recurring | U.S. Agency securities | Level 1 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 0 | 0
Fair Value Measurements Recurring | U.S. Agency securities | Level 2 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 29,330 | 19,264
Fair Value Measurements Recurring | U.S. Agency securities | Level 3 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 0 | 0
Fair Value Measurements Recurring | Certificates of deposit |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 3,365 | 26,509
Fair Value Measurements Recurring | Certificates of deposit | Level 1 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 0 | 0
Fair Value Measurements Recurring | Certificates of deposit | Level 2 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 3,365 | 26,509
Fair Value Measurements Recurring | Certificates of deposit | Level 3 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 0 | 0
Fair Value Measurements Recurring | Corporate debt securities |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 1,684 | 13,848
Fair Value Measurements Recurring | Corporate debt securities | Level 1 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 0 | 0
Fair Value Measurements Recurring | Corporate debt securities | Level 2 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 1,684 | 13,848
Fair Value Measurements Recurring | Corporate debt securities | Level 3 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 0 | 0
Fair Value Measurements Recurring | Commercial paper |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 9,506 | 22,400
Fair Value Measurements Recurring | Commercial paper | Level 1 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 0 | 0
Fair Value Measurements Recurring | Commercial paper | Level 2 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | 9,506 | 22,400
Fair Value Measurements Recurring | Commercial paper | Level 3 |  |
Fair Value (Recurring) [Line Items] |  |
Fair Value | $ 0 | $ 0

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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), classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-2 Reference 2: 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 Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. + References No definition available. + Details
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