Balance Sheet Components - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Prepaid insurance	$ 3,473	$ 206
Prepaid expenses	1,583	694
Receivable from contract manufacturer	53	1,521
Security deposit	1,179	20
Total prepaid and other current assets	$ 6,288	$ 2,441

Receivable From Contract Manufacturer, Current

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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