Summary of Significant Accounting Policies - Schedule of Short-term and Long-term Investment Marketable Securities by Security Type (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Amortized Cost	$ 332,787
Gross Unrealized Gains	24
Gross Unrealized Losses	(139)
Estimated Fair Value	332,672
Long Term Investment
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Amortized Cost	119,768
Gross Unrealized Losses	(131)
Estimated Fair Value	119,637
Long Term Investment \| US Government Notes
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Amortized Cost	27,256
Gross Unrealized Losses	(18)
Estimated Fair Value	27,238
Corporate Note Securities \| Long Term Investment
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Amortized Cost	91,513
Gross Unrealized Losses	(112)
Estimated Fair Value	91,401
Asset-backed Securities \| Long Term Investment
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Amortized Cost	999
Gross Unrealized Losses	(1)
Estimated Fair Value	998
Short Term Investments
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Amortized Cost	213,019	$ 42,010
Gross Unrealized Gains	24	1
Gross Unrealized Losses	(8)	(3)
Estimated Fair Value	213,035	42,008
Short Term Investments \| Corporate Note Securities
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Amortized Cost	79,212	12,780
Gross Unrealized Losses	(8)	(3)
Estimated Fair Value	79,204	12,777
Short Term Investments \| Asset-backed Securities
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Amortized Cost		4,757
Gross Unrealized Gains		1
Estimated Fair Value		4,758
Short Term Investments \| Commercial Paper
Available For Sale Securities Fair Value To Amortized Cost Basis [Line Items]
Amortized Cost	133,807	24,473
Gross Unrealized Gains	24
Estimated Fair Value	$ 133,831	$ 24,473

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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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