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FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Included in cash and cash equivalents: |  |
Amortized Cost | $ 39,771 | $ 31,706
Estimated Fair Value | 39,771 | 31,706
Restricted cash: |  |
Amortized Cost | 364 | 364
Estimated Fair Value | 364 | 364
Marketable securities: |  |
Amortized Cost | 116,142 | 177,675
Gross Unrealized Gains | 6 | 4
Gross Unrealized Losses | (247) | (177)
Estimated Fair Value | 115,901 | 177,502
Money market funds |  |
Included in cash and cash equivalents: |  |
Amortized Cost | 39,771 | 24,207
Estimated Fair Value | 39,771 | 24,207
Restricted cash: |  |
Amortized Cost | 93 | 93
Estimated Fair Value | 93 | 93
Commercial paper |  |
Included in cash and cash equivalents: |  |
Amortized Cost |  | 7,499
Estimated Fair Value |  | 7,499
Certificate of deposit |  |
Restricted cash: |  |
Amortized Cost | 271 | 271
Estimated Fair Value | 271 | 271
U.S. Treasury securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 12,983 | 15,585
Gross Unrealized Losses | (62) | (18)
Estimated Fair Value | 12,921 | 15,567
U.S. Treasury securities (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost |  | 1,524
Gross Unrealized Losses |  | (3)
Estimated Fair Value |  | 1,521
Municipal securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 3,000 |
Gross Unrealized Losses | (24) |
Estimated Fair Value | 2,976 |
Municipal securities (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost |  | 3,000
Gross Unrealized Losses |  | (15)
Estimated Fair Value |  | 2,985
Government-sponsored enterprise securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 9,860 | 12,500
Gross Unrealized Losses | (14) | (7)
Estimated Fair Value | 9,846 | 12,493
Commercial paper (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 64,285 | 84,398
Gross Unrealized Gains | 6 | 2
Gross Unrealized Losses | (92) | (38)
Estimated Fair Value | 64,199 | 84,362
Corporate notes (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 26,014 | 36,444
Gross Unrealized Gains |  | 2
Gross Unrealized Losses | (55) | (17)
Estimated Fair Value | $ 25,959 | 36,429
Corporate notes (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost |  | 24,224
Gross Unrealized Losses |  | (79)
Estimated Fair Value |  | $ 24,145

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