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FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Included in cash and cash equivalents: |  |
Amortized Cost | $ 16,519 | $ 39,771
Estimated Fair Value | 16,519 | 39,771
Restricted cash: |  |
Amortized Cost | 536 | 364
Estimated Fair Value |  | 364
Marketable securities: |  |
Amortized Cost | 351,602 | 116,142
Gross Unrealized Gains | 9 | 6
Gross Unrealized Losses | (972) | (247)
Estimated Fair Value | 350,639 | 115,901
Money market funds |  |
Included in cash and cash equivalents: |  |
Amortized Cost | 12,549 | 39,771
Estimated Fair Value | 12,549 | 39,771
Restricted cash: |  |
Amortized Cost | 264 | 93
Estimated Fair Value | 264 | 93
Commercial paper |  |
Included in cash and cash equivalents: |  |
Amortized Cost | 3,970 |
Estimated Fair Value | 3,970 |
Certificate of deposit |  |
Restricted cash: |  |
Amortized Cost | 272 | 271
Estimated Fair Value | 272 | 271
U.S. Treasury securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost |  | 12,983
Gross Unrealized Losses |  | (62)
Estimated Fair Value |  | 12,921
U.S. Treasury securities - due in 1 to 2 years |  |
Marketable securities: |  |
Amortized Cost | 26,467 |
Gross Unrealized Gains | 1 |
Gross Unrealized Losses | (22) |
Estimated Fair Value | 26,446 |
Municipal securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost |  | 3,000
Gross Unrealized Losses |  | (24)
Estimated Fair Value |  | 2,976
Government-sponsored enterprise securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 94,524 | 9,860
Gross Unrealized Gains | 4 |
Gross Unrealized Losses | (293) | (14)
Estimated Fair Value | 94,235 | 9,846
Government-sponsored enterprise securities (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 10,651 |
Gross Unrealized Losses | (35) |
Estimated Fair Value | 10,616 |
Commercial paper (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 149,583 | 64,285
Gross Unrealized Gains | 1 | 6
Gross Unrealized Losses | (280) | (92)
Estimated Fair Value | 149,304 | 64,199
Corporate notes (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 39,438 | 26,014
Gross Unrealized Gains | 2 |
Gross Unrealized Losses | (160) | (55)
Estimated Fair Value | 39,280 | $ 25,959
Corporate notes (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 30,939 |
Gross Unrealized Gains | 1 |
Gross Unrealized Losses | (182) |
Estimated Fair Value | $ 30,758 |

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