Shareholders' Equity (Details Narrative) $ / shares in Units, $ in Thousands						1 Months Ended		12 Months Ended
	Jul. 31, 2018 USD ($) $ / shares shares	Mar. 28, 2018 USD ($) $ / shares shares	Jul. 21, 2017 USD ($) Integer $ / shares shares	Feb. 17, 2017 USD ($) Integer $ / shares shares	Aug. 29, 2016 USD ($) $ / shares shares	May 31, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares
Preferred stock, shares authorized								5,000,000	5,000,000
Preferred stock par value | $ / shares
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, shares authorized								85,000,000	85,000,000
Common stock par value | $ / shares
Proceeds from issuance of common stock | $								$ 13,592
Common stock, shares issued								40,664,000	31,452,000
Common stock, shares outstanding								40,664,000	31,452,000
Proceeds from exercise of warrants | $									$ 4,074
Warrant exercise agreement, number of forms | Integer			3
Warrants issued								4,035,339
Warrants outstanding								4,035,339
Proceeds from exercise of options | $								$ 58	$ 610
2016 Warrants [Member]
Number of common shares available in each separable unit					1
Number of warrants to purchase stock in each separable unit					1
Number of common shares callable by each warrant					1
Issuance of separable units					3,246,153
Separable units, exercise price | $ / shares					$ 3.25
Proceeds from sale of stock | $					$ 9,800
Common Stock [Member]
Number of shares issued during period								9,192,000
Proceeds from issuance of common stock | $								$ 13,592
Exercise of stock options								20,000	323,000
Proceeds from exercise of options | $								$ 58	$ 610
Minimum [Member]
Warrants exercise price | $ / shares								$ 3.00
Maximum [Member]
Warrants exercise price | $ / shares								5.50
July 2018 Offering Warrants [Member]
Beneficially ownership percentage	4.99%
Warrants exercise price | $ / shares	$ 3.00
Warrant exercise period	5 years
2016 Warrants and New Warrants [Member]
Number of common stock shares called by warrants				625,000
Warrants exercise price | $ / shares				$ 3.25				$ 3.25
Warrant exercise period								5 years
Proceeds from exercise of warrants | $				$ 2,000
New Warrants [Member]
Warrant exercise period								5 years
Noncash charge to shareholder expense included in general and administrative expenses | $				$ 1,100
First Form, Warrant Exercise Agreement, 2016 Warrants [Member]
Number of common stock shares called by warrants			226,923
Warrants exercise price | $ / shares			$ 3.25
Number of warrant holders | Integer			2
First Form, Warrant Exercise Agreement, July 2017 Warrants [Member]
Number of common stock shares called by warrants								226,923
Warrants exercise price | $ / shares								$ 5.50
Warrant exercise period								5 years
Second Form, Warrant Exercise Agreement, 2016 Warrants [Member]
Number of common stock shares called by warrants			540,000
Warrants exercise price | $ / shares			$ 3.25
Number of warrant holders | Integer			1
Second Form, Warrant Exercise Agreement, July 2017 Warrant [Member]
Warrant exercise period								5 years
Second Form, Warrant Exercise Agreement, July 2017 Warrant [Member]
Number of common stock shares called by warrants			270,000
Warrants exercise price | $ / shares			$ 3.25
Third Form, Warrant Exercise Agreement, 2016 Warrants [Member]
Number of common stock shares called by warrants			1,000,000
Warrants exercise price | $ / shares			$ 3.25
Number of warrant holders | Integer			1
Third Form Part1 Warrant Exercise Agreement July 2017 Warrant [Member]
Number of common stock shares called by warrants								500,000
Warrants exercise price | $ / shares								$ 5.50
Warrant exercise period								2 years
Third Form Part2 Warrant Exercise Agreement July 2017 Warrant [Member]
Number of common stock shares called by warrants								500,000
Warrants exercise price | $ / shares								$ 3.25
Warrant exercise period								2 years
July 2017 Warrants [Member]
Number of common stock shares called by warrants			1,496,923
Warrant exercise period								5 years
Proceeds from exercise of warrants | $			$ 5,740
Noncash charge to shareholder expense included in general and administrative expenses | $			$ 3,000
Weighted average price | $ / shares			$ 4.34
July 2018 Offering [Member]
Shares Issued, Price Per Share | $ / shares	$ 2.86
Proceeds from the sale of common stock and warrants | $	$ 3,300
Number of common stock shares called by warrants	1,256,118
Number of common shares available in each separable unit	1
Number of warrants to purchase stock in each separable unit	1
Number of common shares callable by each warrant	1
Investors Group One [Member] | New Warrants [Member]
Number of common stock shares called by warrants				200,000
Warrants exercise price | $ / shares				$ 5.50
One Investor [Member] | New Warrants [Member]
Number of common stock shares called by warrants				212,500
Warrants exercise price | $ / shares				$ 3.25
Number of warrant holders | Integer				1
Securities Purchase Agreement [Member] | Two Accredited Investors [Member]
Proceeds from issuance of common stock | $						$ 2,000	$ 8,000
Beneficially ownership percentage		5.00%
Securities Purchase Agreement [Member] | Two Accredited Investors [Member] | Private Placement [Member]
Number of shares issued during period		7,936,508
Shares Issued, Price Per Share | $ / shares		$ 1.26
Proceeds from issuance of common stock | $		$ 10,000