Supplemental Balance Sheet Information - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Balance Sheet Information [Line Items]
Raw materials and work-in-process inventory		$ 600,000	$ 300,000
Depreciation and amortization		2,197,000	2,449,000	$ 2,940,000
Property and equipment, net		5,845,000	7,315,000
Property and equipment, gross		19,081,000	18,622,000
Accumulated depreciation and amortization for property and equipment		13,236,000	11,307,000
Transfer from other liabilities to accrued expenses and other current liabilities related to fee from debt		2,400,000	1,400,000	$ 585,000
Other accrued expenses		1,900,000	823,000
Accrued payroll and compensation		3,193,000	2,940,000
Transition Agreement [Member]
Supplemental Balance Sheet Information [Line Items]
Other accrued expenses		1,000,000
Accrued payroll and compensation		$ 200,000
T2 Owned Instruments in Service [Member]
Supplemental Balance Sheet Information [Line Items]
Estimated useful lives (in years)		5 years
T2 Owned Instruments in Service [Member] | Product [Member]
Supplemental Balance Sheet Information [Line Items]
Depreciation expense recorded as a component of cost of product revenue		$ 800,000	1,000,000
Finance\Capital Leases Assets [Member]
Supplemental Balance Sheet Information [Line Items]
Property and equipment, net		0
Repurchase of equipment		$ 300,000
Property and equipment, gross			3,600,000
Accumulated depreciation and amortization for property and equipment			2,600,000
T2-Owned Instruments and Components [Member]
Supplemental Balance Sheet Information [Line Items]
Estimated useful lives (in years)		5 years
Property and equipment, gross		$ 6,775,000	6,796,000
Impairment charges	$ 2,600,000
T2 Candida 1.1 Cartridge [Member]
Supplemental Balance Sheet Information [Line Items]
Impairment charges			$ 700,000