Marketable securities - Schedule of Marketable Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Marketable Securities [Line Items]
Debt Securities, Available-for-sale, Amortized Cost, Total	$ 221,610	$ 296,340
Gross unrealized gains	0	0
Gross unrealized losses	(938)	(228)
Fair value	220,672	296,112
U.S. Treasury Bills and Notes [Member]
Marketable Securities [Line Items]
Debt Securities, Available-for-sale, Amortized Cost, Total	215,407	277,559
Gross unrealized gains	0	0
Gross unrealized losses	(930)	(218)
Fair value	214,477	277,341
U.S. Agency Securities [Member]
Marketable Securities [Line Items]
Debt Securities, Available-for-sale, Amortized Cost, Total	6,203	18,781
Gross unrealized gains	0	0
Gross unrealized losses	(8)	(10)
Fair value	$ 6,195	$ 18,771

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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Amount, before tax, of unrealized loss 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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