Balance Sheet Items - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 114	$ 93
Less: accumulated depreciation	(47)	(36)
Property, and equipment, net	67	57
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	78	78
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	32	15
Other Property and Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 4	$ 0

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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