Marketable Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 455,004	$ 149,791
Unrealized Gain	3	120
Unrealized Loss	(2,132)	(8)
Marketable securities	452,875	149,903
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	420,392	125,823
Unrealized Gain	0	47
Unrealized Loss	(2,107)	(6)
Marketable securities	418,285	125,864
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	13,878	4,991
Unrealized Gain	0	0
Unrealized Loss	0	0
Marketable securities	13,878	4,991
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,003	4,294
Unrealized Gain	0	21
Unrealized Loss	(1)	0
Marketable securities	2,002	4,315
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	18,731	14,683
Unrealized Gain	3	52
Unrealized Loss	(24)	(2)
Marketable securities	$ 18,710	$ 14,733

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).

+ References

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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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-Publisher FASB
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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), classified as current.

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