Debt - Long-Term Debt (Detail) - USD ($)	Dec. 31, 2018	Nov. 06, 2018	Dec. 31, 2017	Sep. 01, 2016
Debt Instrument [Line Items]
Notes payable	$ 296,000		$ 200,000
Convertible note	3,000,000
Total	49,306,000		42,874,000
Add: capital leases	126,000		222,000
Less: debt discount	(3,857,000)		(2,023,000)
Total	45,575,000		41,073,000
Less: current portion of long-term debt	(3,276,000)		(3,306,000)
Total long-term debt, net of current portion	42,299,000		37,767,000
Globus facility agreement
Debt Instrument [Line Items]
Maximum borrowing capacity			30,000,000	$ 30,000,000
Term Loan | Squadron Credit Agreement
Debt Instrument [Line Items]
Squadron Term Loan	35,000,000	$ 35,000,000
Amended Credit Facility And Term Loan With Mid Cap
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 11,010,000		$ 12,674,000