Consolidated Balance Sheets (Parenthetical) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Stated value per share	$ 0.01	$ 0.01
Preferred shares authorized	100,000	100,000
Common stock par value	$ 0.006	$ 0.006
Common stock, shares authorized	180,000,000	180,000,000
Common stock issued (in shares)	10,869,530	10,761,684
Common stock, outstanding (in shares)	10,869,530	10,761,684
Series C Convertible Preferred Stock
Stated value per share	$ 0.01	$ 0.01
Preferred shares authorized	1,200	1,200
Preferred stock, liquidation preference, value	$ 5,100	$ 5,100
Preferred stock, shares issued	100	100
Preferred stock outstanding (shares)	100	100
Series D Convertible Preferred Stock
Stated value per share	$ 0.01	$ 0.01
Preferred shares authorized	220	220
Preferred stock, liquidation preference, value	$ 300	$ 300
Preferred stock, shares issued	40	40
Preferred stock outstanding (shares)	40	40
Series E Convertible Preferred Stock
Stated value per share	$ 0.01	$ 0.01
Preferred shares authorized	3,500	3,500
Preferred stock, liquidation preference, value	$ 5,000	$ 5,000
Preferred stock, shares issued	3,478	3,488
Preferred stock outstanding (shares)	3,478	3,488
Series F Convertible Preferred Stock
Stated value per share	$ 0.01	$ 0.01
Preferred shares authorized	2,200	2,200
Preferred stock, liquidation preference, value	$ 5,000	$ 5,000
Preferred stock, shares issued	361	381
Preferred stock outstanding (shares)	361	381