Fair value of financial instruments and investments - Marketable Securities, Unrealized Gains (Losses) (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 73,934	$ 377,287
Gross Unrealized, Gain		107
Gross Unrealized, Loss	(2,934)	(709)
Fair Value	71,000	376,685
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		75,275
Gross Unrealized, Gain		5
Gross Unrealized, Loss		(1)
Fair Value		75,279
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	68,061	268,246
Gross Unrealized, Gain	0	81
Gross Unrealized, Loss	(2,693)	(644)
Fair Value	65,368	267,683
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		15,287
Gross Unrealized, Gain		16
Gross Unrealized, Loss		(5)
Fair Value		15,298
Government obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	5,873	18,479
Gross Unrealized, Gain		5
Gross Unrealized, Loss	(241)	(59)
Fair Value	$ 5,632	$ 18,425

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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount 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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