Property and Equipment - Depreciation and Amortization on Property and Equipment Using the Straight-Line Method (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property Plant And Equipment [Abstract]
Office furniture and fixtures	$ 1,648	$ 1,650
Software	5,525	5,004
Equipment	5,167	4,967
Leasehold improvements	1,658	1,658
Gross property and equipment	13,998	13,279
Less accumulated depreciation and amortization	(11,036)	(10,007)
Property and equipment, net	$ 2,962	$ 3,272

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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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

+ References

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- Definition

Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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- Definition

Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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