Fair Value Measurements - Schedule of Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities	$ 489,557	$ 519,629
Fair Value, Recurring
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Restricted cash	6,112	6,116
Total	522,526	568,927
Fair Value, Recurring \| Money Market Fund
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	26,857	43,182
Fair Value, Recurring \| US government agencies
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	49,357	32,170
Marketable securities, non-current	39,096	47,363
Fair Value, Recurring \| Corporate Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	187,340	192,791
Marketable securities, non-current	47,095	60,652
Fair Value, Recurring \| US Treasuries
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	150,382	169,481
Marketable securities, non-current	16,287	17,172
Fair Value, Recurring \| Level 1
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Restricted cash	6,112	6,116
Total	288,091	315,484
Fair Value, Recurring \| Level 1 \| Money Market Fund
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	26,857	43,182
Fair Value, Recurring \| Level 1 \| US government agencies
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	49,357	32,170
Marketable securities, non-current	39,096	47,363
Fair Value, Recurring \| Level 1 \| Corporate Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current
Marketable securities, non-current
Fair Value, Recurring \| Level 1 \| US Treasuries
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	150,382	169,481
Marketable securities, non-current	16,287	17,172
Fair Value, Recurring \| Level 2
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Restricted cash
Total	234,435	253,443
Fair Value, Recurring \| Level 2 \| Money Market Fund
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents
Fair Value, Recurring \| Level 2 \| US government agencies
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current
Marketable securities, non-current
Fair Value, Recurring \| Level 2 \| Corporate Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current	187,340	192,791
Marketable securities, non-current	47,095	$ 60,652
Fair Value, Recurring \| Level 2 \| US Treasuries
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current
Marketable securities, non-current
Fair Value, Recurring \| Level 3
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Restricted cash
Total
Fair Value, Recurring \| Level 3 \| Money Market Fund
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents
Fair Value, Recurring \| Level 3 \| US government agencies
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current
Marketable securities, non-current
Fair Value, Recurring \| Level 3 \| Corporate Bonds
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current
Marketable securities, non-current
Fair Value, Recurring \| Level 3 \| US Treasuries
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Marketable securities, current
Marketable securities, non-current

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.

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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).

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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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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.

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Amount of investment in marketable security, classified as current.

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Amount of investment in marketable security, classified as noncurrent.

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