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FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Included in cash and cash equivalents: |  |
Amortized Cost | $ 36,824 | $ 16,815
Gross Unrealized Gains | 2 |
Estimated Fair Value | 36,826 | 16,815
Restricted cash: |  |
Amortized Cost | 1,854 | 1,115
Estimated Fair Value | 1,854 | 1,115
Marketable securities: |  |
Amortized Cost | 315,736 | 306,784
Gross Unrealized Gains | 1,010 | 402
Gross Unrealized Losses | (4) | (212)
Estimated Fair Value | 316,742 | 306,974
Money market funds |  |
Included in cash and cash equivalents: |  |
Amortized Cost | 31,854 | 16,815
Estimated Fair Value | 31,854 | 16,815
Restricted cash: |  |
Amortized Cost | 1,581 | 843
Estimated Fair Value | 1,581 | 843
Commercial paper |  |
Included in cash and cash equivalents: |  |
Amortized Cost | 4,970 |
Gross Unrealized Gains | 2 |
Estimated Fair Value | 4,972 |
Certificate of deposit |  |
Restricted cash: |  |
Amortized Cost | 273 | 272
Estimated Fair Value | 273 | 272
U.S. Treasury securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 35,481 | 26,752
Gross Unrealized Gains | 56 | 95
Estimated Fair Value | 35,537 | 26,847
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
Government-sponsored enterprise securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 19,680 | 86,250
Gross Unrealized Gains | 27 | 43
Gross Unrealized Losses |  | (92)
Estimated Fair Value | 19,707 | 86,201
Government-sponsored enterprise securities (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 5,000 | 13,598
Gross Unrealized Gains |  | 72
Estimated Fair Value | 5,000 | 13,670
Commercial paper (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 135,717 | 102,270
Gross Unrealized Gains | 327 | 31
Gross Unrealized Losses | (1) | (33)
Estimated Fair Value | 136,043 | 102,268
Corporate notes (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 87,816 | 48,409
Gross Unrealized Gains | 327 | 14
Gross Unrealized Losses | (2) | (63)
Estimated Fair Value | 88,141 | 48,360
Corporate notes (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 32,042 | 26,628
Gross Unrealized Gains | 273 | 130
Gross Unrealized Losses | (1) | (24)
Estimated Fair Value | $ 32,314 | $ 26,734

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