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Cash Equivalents and Marketable Securities - Schedule of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 | Sep. 30, 2022
--- | --- | --- | ---
Cash And Cash Equivalents [Line Items] |  |  |
Amortized Cost Basis | $ 318,979 | $ 299,026 |
Unrealized Gains | 19 | 10 |
Unrealized Losses | (12) | (626) |
Fair Value | 318,986 | 298,410 |
Less amounts classified as cash equivalents, Amortized Cost Basis | (81,834) | (47,254) | $ (96,779)
Marketable Securities |  |  |
Cash And Cash Equivalents [Line Items] |  |  |
Amortized Cost Basis | 239,268 | 255,708 |
Unrealized Gains | 17 | 8 |
Unrealized Losses | (11) | (626) |
Fair Value | 239,274 | 255,090 |
Cash Equivalents |  |  |
Cash And Cash Equivalents [Line Items] |  |  |
Less amounts classified as cash equivalents, Amortized Cost Basis | (79,711) | (43,318) |
Less amounts classified as cash equivalents, Unrealized Gains | (2) | (2) |
Less amounts classified as cash equivalents, Unrealized Losses | 1 |  |
Less amounts classified as cash equivalents, Fair Value | (79,712) | (43,320) |
Money Market Funds |  |  |
Cash And Cash Equivalents [Line Items] |  |  |
Amortized Cost Basis | 54,078 | 36,486 |
Fair Value | 54,078 | 36,486 |
Commercial Paper |  |  |
Cash And Cash Equivalents [Line Items] |  |  |
Amortized Cost Basis | 78,348 | 87,140 |
Fair Value | 78,348 | 87,140 |
Corporate Debt Securities |  |  |
Cash And Cash Equivalents [Line Items] |  |  |
Amortized Cost Basis | 54,501 | 36,554 |
Unrealized Gains | 4 | 2 |
Unrealized Losses | (11) | (127) |
Fair Value | 54,494 | 36,429 |
Asset-backed Securities |  |  |
Cash And Cash Equivalents [Line Items] |  |  |
Amortized Cost Basis | 27,743 | 14,026 |
Unrealized Gains | 8 |  |
Unrealized Losses | (1) | (10) |
Fair Value | 27,750 | 14,016 |
U.S. Government Securities |  |  |
Cash And Cash Equivalents [Line Items] |  |  |
Amortized Cost Basis | 104,309 | 91,619 |
Unrealized Gains | 7 | 8 |
Unrealized Losses |  | (376) |
Fair Value | $ 104,316 | 91,251 |
U.S. Agency Securities |  |  |
Cash And Cash Equivalents [Line Items] |  |  |
Amortized Cost Basis |  | 16,646 |
Unrealized Losses |  | (39) |
Fair Value |  | 16,607 |
Supranational Debt Securities |  |  |
Cash And Cash Equivalents [Line Items] |  |  |
Amortized Cost Basis |  | 16,555 |
Unrealized Losses |  | (74) |
Fair Value |  | $ 16,481 |

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