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FAIR VALUE MEASUREMENTS - Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Included in cash and cash equivalents: |  |
Amortized Cost | $ 35,228 | $ 50,193
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | (1)
Fair Value | 35,228 | 50,192
Restricted cash: |  |
Restricted cash | 1,876 | 1,860
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | 1,876 | 1,860
Marketable securities: |  |
Amortized Cost | 341,116 | 421,790
Gross Unrealized Gains | 390 | 470
Gross Unrealized Losses | (28) | (191)
Fair Value | 341,478 | 422,069
Money market funds |  |
Included in cash and cash equivalents: |  |
Amortized Cost | 30,264 | 45,215
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | 30,264 | 45,215
Restricted cash: |  |
Restricted cash | 1,602 | 1,587
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | 1,602 | 1,587
Commercial paper |  |
Included in cash and cash equivalents: |  |
Amortized Cost | 4,964 | 4,978
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | (1)
Fair Value | 4,964 | 4,977
Certificate of deposit |  |
Restricted cash: |  |
Restricted cash | 274 | 273
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | 0 | 0
Fair Value | 274 | 273
U.S. Treasury securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 22,836 | 7,937
Gross Unrealized Gains | 45 | 22
Gross Unrealized Losses | 0 | 0
Fair Value | 22,881 | 7,959
U.S. Treasury securities (due in 1-2 years) |  |
Marketable securities: |  |
Amortized Cost | 0 | 22,620
Gross Unrealized Gains | 0 | 1
Gross Unrealized Losses | 0 | (11)
Fair Value | 0 | 22,610
Municipal securities (due in 1 to 2 years) |  |
Marketable securities: |  |
Amortized Cost | 5,041 |
Gross Unrealized Gains | 13 |
Gross Unrealized Losses | 0 |
Fair Value | 5,054 |
Government-sponsored enterprise securities (due in 1-2 years) |  |
Marketable securities: |  |
Amortized Cost | 5,000 |
Gross Unrealized Gains | 0 |
Gross Unrealized Losses | 0 |
Fair Value | 5,000 |
Government-sponsored enterprise securities (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost |  | 8,741
Gross Unrealized Gains |  | 7
Gross Unrealized Losses |  | 0
Fair Value |  | 8,748
Commercial paper (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 118,244 | 180,131
Gross Unrealized Gains | 34 | 150
Gross Unrealized Losses | (4) | (56)
Fair Value | 118,274 | 180,225
Corporate notes (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 161,050 | 130,361
Gross Unrealized Gains | 218 | 284
Gross Unrealized Losses | (8) | (27)
Fair Value | 161,260 | 130,618
Corporate notes (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 28,945 | 72,000
Gross Unrealized Gains | 80 | 6
Gross Unrealized Losses | (16) | (97)
Fair Value | $ 29,009 | $ 71,909

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