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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Schedule of Debt Investments (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | $ 637,466 | $ 302,707
Cash and cash equivalents |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | 174,585 | 18,001
Cash and cash equivalents | Level 1 | Money market funds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | 174,585 | 12,009
Cash and cash equivalents | Level 2 | Commercial paper and certificates of deposit |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | 0 | 5,992
Short-term investments |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | 462,881 | 284,706
Short-term investments | Level 1 | U.S. government securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | 42,132 | 56,835
Short-term investments | Level 2 | U.S. agency securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | 25,744 | 9,530
Short-term investments | Level 2 | Commercial paper and certificates of deposit |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | 0 | 4,466
Short-term investments | Level 2 | Corporate bonds |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | 392,585 | 213,875
Short-term investments | Level 2 | Asset-backed securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Total debt investments | $ 2,420 | $ 0

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