Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Short-term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 94,966	$ 15,125
Gross unrealized losses	(595)	(15)
Fair value	94,371	15,110
U.S. Treasury bonds
Debt Securities, Available-for-sale [Line Items]
Amortized cost	47,595	10,142
Gross unrealized losses	(458)	(13)
Fair value	47,137	10,129
US Treasury Bill
Debt Securities, Available-for-sale [Line Items]
Amortized cost	47,371	4,983
Gross unrealized losses	(137)	(2)
Fair value	47,234	4,981
Long-term investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	23,140	9,966
Gross unrealized gains	16
Gross unrealized losses	(340)
Fair value	22,816	9,966
US Treasury Notes
Debt Securities, Available-for-sale [Line Items]
Amortized cost	21,971	9,966
Gross unrealized gains	16
Gross unrealized losses	(335)
Fair value	21,652	$ 9,966
Certificates of Deposit
Debt Securities, Available-for-sale [Line Items]
Amortized cost	1,169
Gross unrealized losses	(5)
Fair value	$ 1,164

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amortized cost of 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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