Short-Term Investments (Details) $ in Thousands	Jun. 30, 2022 USD ($) item	Dec. 31, 2021 USD ($) item
Short-term Investments
Short-Term Investments
Amortized Cost	$ 72,838	$ 39,000
Gross Unrealized Losses	(186)
Fair Value	$ 72,652	$ 39,000
Number of short term investments in unrealized loss position for less than 12 months \| item	21
Aggregate value of short term investments in unrealized loss position for less than 12 months	$ 42,900
Number of short term investments in unrealized loss position \| item		0
Corporate debt securities
Short-Term Investments
Amortized Cost	23,808
Gross Unrealized Losses	(123)
Fair Value	23,685
Commercial paper
Short-Term Investments
Amortized Cost	8,991
Gross Unrealized Losses	(7)
Fair Value	8,984
Yankee securities
Short-Term Investments
Amortized Cost	7,039
Gross Unrealized Losses	(41)
Fair Value	6,998
U.S. agency bonds
Short-Term Investments
Amortized Cost	3,000
Gross Unrealized Losses	(15)
Fair Value	2,985
Reverse repurchase agreements
Short-Term Investments
Amortized Cost	30,000	$ 39,000
Fair Value	$ 30,000	$ 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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