Short-Term Investments (Details) $ in Thousands	Mar. 31, 2023 USD ($) item	Dec. 31, 2022 USD ($) item
Short-term Investments
Short-Term Investments
Amortized Cost	$ 11,031	$ 205,991
Gross Unrealized Gains	3
Gross Unrealized Losses	(7)	(79)
Fair Value	$ 11,027	$ 205,912
Number of short term investments in unrealized loss position for less than 12 months \| item	3	16
Aggregate value of short term investments in unrealized loss position for less than 12 months	$ 6,200	$ 25,600
Corporate debt securities
Short-Term Investments
Amortized Cost	6,082	16,508
Gross Unrealized Losses	(7)	(63)
Fair Value	6,075	16,445
Treasury bills
Short-Term Investments
Amortized Cost	4,949	5,983
Gross Unrealized Gains	3
Gross Unrealized Losses		(3)
Fair Value	$ 4,952	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		178,500
Fair Value		$ 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).

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