Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($)		Total	Cumulative Effect, Period of Adoption, Adjustment	Preferred Stock	Common Stock		Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment
Balance at the beginning of the period (in shares) at Dec. 31, 2018	[1]				2,418,000
Balance at the beginning of the period at Dec. 31, 2018		$ 11,052,000	$ (186,000)		$ 0		$ 128,368,000	$ (1,000)	$ (117,315,000)	$ (186,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under employee stock option and stock purchase plans (in shares)	[1]				30,000
Stock-based compensation		543,000					543,000
Net loss from continuing operations		(2,865,000)							(2,865,000)
Common stock withheld in lieu of income tax withholding on vesting of restricted stock units (in shares)	[1]				(10,000)
Common stock withheld in lieu of income tax withholding on vesting of restricted stock units		(111,000)					(111,000)
Balance at the end of the period (in shares) at Mar. 31, 2019	[1]				2,438,000
Balance at the end of the period at Mar. 31, 2019		8,433,000			$ 0		128,800,000	(1,000)	(120,366,000)
Balance at the beginning of the period (in shares) at Dec. 31, 2018	[1]				2,418,000
Balance at the beginning of the period at Dec. 31, 2018		11,052,000	$ (186,000)		$ 0		128,368,000	(1,000)	(117,315,000)	$ (186,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss from continuing operations		(5,119,000)
Foreign currency translation adjustments		(2,000)
Balance at the end of the period (in shares) at Jun. 30, 2019	[1]				2,474,000
Balance at the end of the period at Jun. 30, 2019		6,152,000			$ 0		128,775,000	(3,000)	(122,620,000)
Balance at the beginning of the period (in shares) at Mar. 31, 2019	[1]				2,438,000
Balance at the beginning of the period at Mar. 31, 2019		8,433,000			$ 0		128,800,000	(1,000)	(120,366,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under employee stock option and stock purchase plans (in shares)	[1]				36,000
Stock-based compensation		(20,000)					(20,000)
Net loss from continuing operations		(2,254,000)							(2,254,000)
Common stock withheld in lieu of income tax withholding on vesting of restricted stock units		(5,000)					(5,000)
Foreign currency translation adjustments		(2,000)						(2,000)
Balance at the end of the period (in shares) at Jun. 30, 2019	[1]				2,474,000
Balance at the end of the period at Jun. 30, 2019		6,152,000			$ 0		128,775,000	(3,000)	(122,620,000)
Balance at the beginning of the period (in shares) at Dec. 31, 2019				0	2,486,000	[1]
Balance at the beginning of the period at Dec. 31, 2019		3,996,000		$ 0	$ 0		128,873,000	(3,000)	(124,874,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under employee stock option and stock purchase plans (in shares)	[1]				5,000
Issuance of common stock under employee stock option and stock purchase plans		0
Issuance of common stock and warrants (in shares)	[1]				688,000
Issuance of common stock and warrants		2,749,000					2,749,000
Offering costs on issuance of common stock and warrants		(474,000)					(474,000)
Warrant liability		(1,636,000)					(1,636,000)
Conversion of notes to preferred stock (in shares)				(2,709,000)
Conversion of notes to preferred stock		1,769,000					1,769,000
Stock-based compensation		20,000					20,000
Net loss from continuing operations		(541,000)							(541,000)
Balance at the end of the period (in shares) at Mar. 31, 2020				2,709,000	3,179,000	[1]
Balance at the end of the period at Mar. 31, 2020		5,883,000		$ 0	$ 0		131,301,000	(3,000)	(125,415,000)
Balance at the beginning of the period (in shares) at Dec. 31, 2019				0	2,486,000	[1]
Balance at the beginning of the period at Dec. 31, 2019		3,996,000		$ 0	$ 0		128,873,000	(3,000)	(124,874,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss from continuing operations		(4,881,000)
Issuance of common stock upon the exercise of warrants		15,000
Foreign currency translation adjustments		0
Balance at the end of the period (in shares) at Jun. 30, 2020				2,597,000	3,216,000	[1]
Balance at the end of the period at Jun. 30, 2020		1,714,000		$ 0	$ 0		131,472,000	(3,000)	(129,755,000)
Balance at the beginning of the period (in shares) at Mar. 31, 2020				2,709,000	3,179,000	[1]
Balance at the beginning of the period at Mar. 31, 2020		5,883,000		$ 0	$ 0		131,301,000	(3,000)	(125,415,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under employee stock option and stock purchase plans (in shares)	[1]				0
Issuance of common stock under employee stock option and stock purchase plans		30,000					30,000
Conversion of notes to preferred stock (in shares)				(111,548)
Conversion of notes to preferred stock	[1]	22,310
Stock-based compensation		41,000					41,000
Net loss from continuing operations		(4,340,000)							(4,340,000)
Common stock withheld in lieu of income tax withholding on vesting of restricted stock units		(3,000)					(3,000)
Issuance of common stock upon the exercise of warrants		103,000			$ 15,000	[1]	103,000
Foreign currency translation adjustments		0
Balance at the end of the period (in shares) at Jun. 30, 2020				2,597,000	3,216,000	[1]
Balance at the end of the period at Jun. 30, 2020		$ 1,714,000		$ 0	$ 0		$ 131,472,000	$ (3,000)	$ (129,755,000)

[1] * Shares outstanding for prior periods have been restated for the 1-for-5 reverse stock split