Short-Term Investments (Details) $ in Thousands	Dec. 31, 2023 USD ($) item	Dec. 31, 2022 USD ($) item
Short-term Investments
Short-Term Investments
Amortized Cost	$ 71,000	$ 205,991
Gross Unrealized Losses		(79)
Fair Value	$ 71,000	$ 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	$ 71,000	178,500
Fair Value	$ 71,000	$ 178,500

Amortized cost, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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