Supplemental Balance Sheet Information - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20,934	$ 20,107
Less accumulated depreciation and amortization	(16,200)	(15,432)
Property and equipment, net	4,734	4,675
Office and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	749	749
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	783	783
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,573	5,507
Furniture [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	197	197
Manufacturing Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,445	1,445
Manufacturing Tooling and Molds [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	478	478
T2-Owned Instruments and Components [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	7,150	6,668
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,785	3,768
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 774	$ 512

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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