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FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Included in cash and cash equivalents: |  |
Amortized Cost | $ 34,417 | $ 39,771
Estimated Fair Value | 34,417 | 39,771
Restricted cash: |  |
Amortized Cost | 535 | 364
Estimated Fair Value | 535 | 364
Marketable securities: |  |
Amortized Cost | 343,708 | 116,142
Gross Unrealized Gains | 28 | 6
Gross Unrealized Losses | (980) | (247)
Estimated Fair Value | 342,756 | 115,901
Money market funds |  |
Included in cash and cash equivalents: |  |
Amortized Cost | 34,417 | 39,771
Estimated Fair Value | 34,417 | 39,771
Restricted cash: |  |
Amortized Cost | 263 | 93
Estimated Fair Value | 263 | 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 |  | 12,983
Gross Unrealized Losses |  | (62)
Estimated Fair Value |  | 12,921
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 | 78,280 | 9,860
Gross Unrealized Gains | 20 |
Gross Unrealized Losses | (224) | (14)
Estimated Fair Value | 78,076 | 9,846
Government-sponsored enterprise securities (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 18,680 |
Gross Unrealized Losses | (141) |
Estimated Fair Value | 18,539 |
Commercial paper (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 202,540 | 64,285
Gross Unrealized Gains | 7 | 6
Gross Unrealized Losses | (365) | (92)
Estimated Fair Value | 202,182 | 64,199
Corporate notes (due in less than one year) |  |
Marketable securities: |  |
Amortized Cost | 34,354 | 26,014
Gross Unrealized Gains | 1 |
Gross Unrealized Losses | (138) | (55)
Estimated Fair Value | 34,217 | $ 25,959
Corporate notes (due in one to two years) |  |
Marketable securities: |  |
Amortized Cost | 9,854 |
Gross Unrealized Losses | (112) |
Estimated Fair Value | $ 9,742 |

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 + Details
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