Fair Value Measurements - Schedule of Assets Measured at Fair Value on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Restricted cash	$ 5,794	$ 6,130
Total	0	547,780
Money Market Fund
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	54,291	50,551
US government agencies
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	13,883
Marketable securities, current	141,331	120,467
Marketable securities, non-current	50,200	58,653
Commercial Paper
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	8,937
Corporate Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	109,326	144,259
Marketable securities, non-current	26,788	73,871
US Treasuries
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	26,117	74,045
Marketable securities, non-current		19,804
Level 1
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Restricted cash	5,794	6,130
Total	109,022	150,530
Level 1 \| Money Market Fund
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	54,291	50,551
Level 1 \| US government agencies
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	13,883
Marketable securities, current		0
Marketable securities, non-current		0
Level 1 \| Commercial Paper
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	8,937
Level 1 \| Corporate Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current		0
Marketable securities, non-current		0
Level 1 \| US Treasuries
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	26,117	74,045
Marketable securities, non-current		19,804
Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Restricted cash
Total	327,645	397,250
Level 2 \| Money Market Fund
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents		0
Level 2 \| US government agencies
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents
Marketable securities, current	141,331	120,467
Marketable securities, non-current	50,200	58,653
Level 2 \| Commercial Paper
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents
Level 2 \| Corporate Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	109,326	144,259
Marketable securities, non-current	26,788	73,871
Level 2 \| US Treasuries
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current		0
Marketable securities, non-current		0
Level 3
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Restricted cash
Total	0	0
Level 3 \| Money Market Fund
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents		0
Level 3 \| US government agencies
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents
Marketable securities, current		0
Marketable securities, non-current		0
Level 3 \| Commercial Paper
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents
Level 3 \| Corporate Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current		0
Marketable securities, non-current		0
Level 3 \| US Treasuries
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current		0
Marketable securities, non-current		$ 0

Restricted cash fair value.

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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

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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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Amount of investment in marketable security, classified as current.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

Amount of investment in marketable security, classified as noncurrent.

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