Short-Term Investments (Details) $ in Thousands	Mar. 31, 2022 USD ($) item	Dec. 31, 2021 USD ($)
Short-term Investments
Short-Term Investments
Amortized Cost	$ 66,182	$ 39,000
Gross Unrealized Losses	(53)
Fair Value	$ 66,129	39,000
Number of short term investments in unrealized loss position for less than 12 months \| item	15
Aggregate value of short term investments in unrealized loss position for less than 12 months	$ 26,300
Corporate debt securities
Short-Term Investments
Amortized Cost	17,157
Gross Unrealized Losses	(36)
Fair Value	17,121
Commercial paper
Short-Term Investments
Amortized Cost	5,987
Gross Unrealized Losses	(7)
Fair Value	5,980
Yankee securities
Short-Term Investments
Amortized Cost	4,039
Gross Unrealized Losses	(10)
Fair Value	4,029
Treasury Bills
Short-Term Investments
Amortized Cost	1,999
Fair Value	1,999
Reverse repurchase agreements
Short-Term Investments
Amortized Cost	37,000	39,000
Fair Value	$ 37,000	$ 39,000

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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