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FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Included in cash and cash equivalents: |  |
Amortized Cost | $ 16,815 | $ 39,771
Estimated Fair Value | 16,815 | 39,771
Restricted cash: |  |
Amortized Cost | 1,115 | 364
Estimated Fair Value | 1,115 | 364
Marketable securities: |  |
Amortized Cost | 306,784 | 116,142
Gross Unrealized Gains | 402 | 6
Gross Unrealized Losses | (212) | (247)
Estimated Fair Value | 306,974 | 115,901
Money market funds |  |
Included in cash and cash equivalents: |  |
Amortized Cost | 16,815 | 39,771
Estimated Fair Value | 16,815 | 39,771
Restricted cash: |  |
Amortized Cost | 843 | 93
Estimated Fair Value | 843 | 93
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 | 26,752 | 12,983
Gross Unrealized Gains | 95 |
Gross Unrealized Losses |  | (62)
Estimated Fair Value | 26,847 | 12,921
U.S. Treasury securities (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 2,877 |
Gross Unrealized Gains | 17 |
Estimated Fair Value | 2,894 |
Municipal securities (due in one to two years) |  |
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 | 86,250 | 9,860
Gross Unrealized Gains | 43 |
Gross Unrealized Losses | (92) | (14)
Estimated Fair Value | 86,201 | 9,846
Government-sponsored enterprise securities (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 13,598 |
Gross Unrealized Gains | 72 |
Estimated Fair Value | 13,670 |
Commercial paper (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 102,270 | 64,285
Gross Unrealized Gains | 31 | 6
Gross Unrealized Losses | (33) | (92)
Estimated Fair Value | 102,268 | 64,199
Corporate notes (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 48,409 | 26,014
Gross Unrealized Gains | 14 |
Gross Unrealized Losses | (63) | (55)
Estimated Fair Value | 48,360 | $ 25,959
Corporate notes (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 26,628 |
Gross Unrealized Gains | 130 |
Gross Unrealized Losses | (24) |
Estimated Fair Value | $ 26,734 |

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