Balance Sheet Components - Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Balance Sheet Components [Abstract]
Prepaid expenses	$ 1,794	$ 1,794
Deferred offering costs	2,505
Prepaid insurance	271	122
Other current assets	170	363
Total prepaid expenses and other current assets	$ 4,740	$ 2,279

Specific incremental costs directly attributable to a proposed or actual offering of securities which are deferred at the end of the reporting period.

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Amount of current assets classified as other.

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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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Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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Balance sheet components.

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