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Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Tax benefit at federal statutory rate	$ (39,948)	$ (22,081)	$ (10,972)
State income taxes	(16,570)	(4,694)
Tax credits	(8,010)	(6,530)	(2,387)
Uncertain tax positions	2,003	2,044	708
Stock-based compensation	353	1,493	1,251
Nondeductible expense	51	124	58
Tax benefit recognized on utilization of attributes previous reserved		(13,582)
Deferred adjustment from amended tax return		(1,073)
Change in valuation allowance	62,280	44,748	11,346
Others	$ (159)	$ (449)	$ (4)

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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