Marketable securities - Schedule of Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Marketable Securities [Line Items]
Debt Securities, Available-for-sale, Amortized Cost, Total	$ 232,611	$ 296,340
Gross unrealized gains	0	0
Gross unrealized losses	(732)	(228)
Fair value	231,879	296,112
U.S. Treasury Bills and Notes [Member]
Marketable Securities [Line Items]
Debt Securities, Available-for-sale, Amortized Cost, Total	218,875	277,559
Gross unrealized gains	0	0
Gross unrealized losses	(711)	(218)
Fair value	218,164	277,341
U.S. Agency Securities [Member]
Marketable Securities [Line Items]
Debt Securities, Available-for-sale, Amortized Cost, Total	13,736	18,781
Gross unrealized gains	0	0
Gross unrealized losses	(21)	(10)
Fair value	$ 13,715	$ 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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