Supplemental Financial Information - Schedule of Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Disclosure Of Prepaid Expenses And Other Current Assets [Line Items]
Prepaid Insurance	$ 2,299	$ 5
Research and development service agreements	2,077	432
Prepaid raw materials	248	91
Other	216	15
Total prepaid expenses and other current assets	$ 4,840	$ 543

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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Name:	us-gaap_PrepaidInsurance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant