Liquidity, Financial Condition and Management's Plans - Additional Information (Detail) - USD ($)				3 Months Ended		6 Months Ended
	Jul. 18, 2017	Mar. 07, 2017	Jan. 27, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Liquidity And Managements Plans [Line Items]
Net loss				$ (3,966,000)	$ (3,513,000)	$ (6,856,000)	$ (6,702,000)
Accumulated deficit				105,167,000		105,167,000		$ 98,312,000
Positive (deficit) in working capital				$ 6,700,000		6,700,000
Net cash used in continuing operating activities						(3,519,000)	(5,953,000)
Shares issued for an investment (in shares)		8,333,333
Proceeds from issuance of common stock						$ 10,000,000	$ 70,000
Aspire Capital Fund, LLC [Member]
Liquidity And Managements Plans [Line Items]
Maximum commitment under stock purchase agreement			$ 17,000,000
Agreement term			30 months
Shares issued during period (in shares)		2,083,333	708,333
Proceeds from issuance of common stock		$ 2,000,000	$ 2,000,000
Essentialis, Inc. [Member]
Liquidity And Managements Plans [Line Items]
Proceeds from issuance of common stock		$ 8,000,000
Subsequent Event [Member] | NeoForce Holdings Inc. [Member]
Liquidity And Managements Plans [Line Items]
Proceeds from the sale of business	$ 720,000