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Cash Equivalents and Marketable Securities - Schedule of Cash Equivalent and Marketable Securities Classified as Available-for-Sale (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
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Cash And Cash Equivalents [Line Items] |  |
Amortized Cost Basis Cash Equivalents | $ 257,318 | $ 233,103
Unrealized Losses | (25) | (2)
Cash Equivalents, Estimated Fair Value | 257,293 | 233,101
Amortized Cost Basis | 476,186 | 626,976
Unrealized Gains | 1 | 2
Unrealized Losses | (428) | (134)
Estimated Fair Value | 475,759 | 626,844
Commercial Paper |  |
Cash And Cash Equivalents [Line Items] |  |
Amortized Cost Basis Cash Equivalents | 122,812 | 56,988
Unrealized Losses | (21) | (2)
Cash Equivalents, Estimated Fair Value | 122,791 | 56,986
Agency Discount Notes |  |
Cash And Cash Equivalents [Line Items] |  |
Amortized Cost Basis Cash Equivalents | 34,937 |
Unrealized Losses | (4) |
Cash Equivalents, Estimated Fair Value | 34,933 |
Money Market Funds |  |
Cash And Cash Equivalents [Line Items] |  |
Amortized Cost Basis Cash Equivalents | 99,569 | 176,115
Cash Equivalents, Estimated Fair Value | 99,569 | 176,115
Marketable Securities |  |
Cash And Cash Equivalents [Line Items] |  |
Amortized Cost Basis | 218,868 | 393,873
Unrealized Gains | 1 | 2
Unrealized Losses | (403) | (132)
Estimated Fair Value | 218,466 | 393,743
Marketable Securities | U.S. Treasury Notes |  |
Cash And Cash Equivalents [Line Items] |  |
Amortized Cost Basis | 76,127 | 76,518
Unrealized Losses | (151) | (46)
Estimated Fair Value | 75,976 | 76,472
Marketable Securities | Commercial Paper |  |
Cash And Cash Equivalents [Line Items] |  |
Amortized Cost Basis | 126,709 | 167,761
Unrealized Gains | 1 | 2
Unrealized Losses | (207) | (26)
Estimated Fair Value | 126,503 | 167,737
Marketable Securities | Corporate Debt Securities |  |
Cash And Cash Equivalents [Line Items] |  |
Amortized Cost Basis | 16,032 | 122,548
Unrealized Losses | (45) | (58)
Estimated Fair Value | $ 15,987 | 122,490
Marketable Securities | Supranational Debt Securities |  |
Cash And Cash Equivalents [Line Items] |  |
Amortized Cost Basis |  | 27,046
Unrealized Losses |  | (2)
Estimated Fair Value |  | $ 27,044

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