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Fair Value of Financial Assets and Liabilities - Marketable Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Fair Value of Financial Assets |  |
Amortized Cost | $ 234,842 | $ 205,702
Gross Unrealized Gains | 11 |
Gross Unrealized Losses | (185) | (91)
Fair Value | 234,668 | 205,611
Corporate debt securities and commercial paper |  |
Fair Value of Financial Assets |  |
Amortized Cost | 234,842 | 205,702
Gross Unrealized Gains | 11 |
Gross Unrealized Losses | (185) | (91)
Fair Value | $ 234,668 | $ 205,611

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