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Short-Term Investments (Details) $ in Thousands | Sep. 30, 2023 USD ($) item | Dec. 31, 2022 USD ($) item
--- | --- | ---
Short-term Investments |  |
Short-Term Investments |  |
Amortized Cost | $ 69,000 | $ 205,991
Gross Unrealized Losses |  | (79)
Fair Value | $ 69,000 | $ 205,912
Number of short term investments in unrealized loss position for less than 12 months | item | 0 | 16
Aggregate value of short term investments in unrealized loss position for less than 12 months |  | $ 25,600
Corporate debt securities |  |
Short-Term Investments |  |
Amortized Cost |  | 16,508
Gross Unrealized Losses |  | (63)
Fair Value |  | 16,445
Treasury bills |  |
Short-Term Investments |  |
Amortized Cost |  | 5,983
Gross Unrealized Losses |  | (3)
Fair Value |  | 5,980
Yankee securities |  |
Short-Term Investments |  |
Amortized Cost |  | 2,000
Gross Unrealized Losses |  | (1)
Fair Value |  | 1,999
U.S. agency bonds |  |
Short-Term Investments |  |
Amortized Cost |  | 3,000
Gross Unrealized Losses |  | (12)
Fair Value |  | 2,988
Reverse repurchase agreements |  |
Short-Term Investments |  |
Amortized Cost | $ 69,000 | 178,500
Fair Value | $ 69,000 | $ 178,500

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