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Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Financial assets: |  |
Marketable securities | $ 501,111 | $ 544,787
Marketable equity securities | 1,535 |
Total financial assets | 502,646 | 544,787
Financial liabilities: |  |
Success payment liabilities | 2,544 | 1,576
Total financial liabilities | 2,544 | 1,576
U.S. Treasury securities |  |
Financial assets: |  |
Marketable securities | 343,194 | 374,356
U.S. government agency securities |  |
Financial assets: |  |
Marketable securities | 38,427 | 48,750
Corporate debt securities |  |
Financial assets: |  |
Marketable securities | 68,682 | 59,606
Money market funds |  |
Financial assets: |  |
Money market funds | 50,808 | 62,075
Level 1 |  |
Financial assets: |  |
Marketable equity securities | 1,535 |
Total financial assets | 52,343 | 62,075
Financial liabilities: |  |
Success payment liabilities | 0 | 0
Total financial liabilities | 0 | 0
Level 1 | U.S. Treasury securities |  |
Financial assets: |  |
Marketable securities | 0 | 0
Level 1 | U.S. government agency securities |  |
Financial assets: |  |
Marketable securities | 0 | 0
Level 1 | Corporate debt securities |  |
Financial assets: |  |
Marketable securities | 0 | 0
Level 1 | Money market funds |  |
Financial assets: |  |
Money market funds | 50,808 | 62,075
Level 2 |  |
Financial assets: |  |
Marketable equity securities | 0 |
Total financial assets | 450,303 | 482,712
Financial liabilities: |  |
Success payment liabilities | 0 | 0
Total financial liabilities | 0 | 0
Level 2 | U.S. Treasury securities |  |
Financial assets: |  |
Marketable securities | 343,194 | 374,356
Level 2 | U.S. government agency securities |  |
Financial assets: |  |
Marketable securities | 38,427 | 48,750
Level 2 | Corporate debt securities |  |
Financial assets: |  |
Marketable securities | 68,682 | 59,606
Level 2 | Money market funds |  |
Financial assets: |  |
Money market funds | 0 | 0
Level 3 |  |
Financial assets: |  |
Marketable equity securities | 0 |
Total financial assets | 0 | 0
Financial liabilities: |  |
Success payment liabilities | 2,544 | 1,576
Total financial liabilities | 2,544 | 1,576
Level 3 | U.S. Treasury securities |  |
Financial assets: |  |
Marketable securities | 0 | 0
Level 3 | U.S. government agency securities |  |
Financial assets: |  |
Marketable securities | 0 | 0
Level 3 | Corporate debt securities |  |
Financial assets: |  |
Marketable securities | 0 | 0
Level 3 | Money market funds |  |
Financial assets: |  |
Money market funds | $ 0 | $ 0

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