Short-term Investments - Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 237,700	$ 28,800
Gross unrealized gains	10	83
Gross unrealized losses	(72)	0
Fair value	237,638	28,883
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized cost	182,739	22,338
Gross unrealized gains	7	71
Gross unrealized losses	(51)	0
Fair value	182,695	22,409
Government-related debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized cost	28,104	5,000
Gross unrealized gains	0	3
Gross unrealized losses	(18)	0
Fair value	28,086	5,003
Asset-backed Securities
Debt Securities, Available-for-sale [Line Items]
Amortized cost	26,857	1,462
Gross unrealized gains	3	9
Gross unrealized losses	(3)	0
Fair value	$ 26,857	$ 1,471

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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-Section 50
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-Subparagraph (b)
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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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-Publisher FASB
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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-Publisher FASB
-Name Accounting Standards Codification
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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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