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CONSOLIDATED CONDENSED STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT) (UNAUDITED) - USD ($) $ in Thousands | Total | Series C Convertible Preferred Stock [Member] | Convertible Preferred Stock [Member] | Convertible Preferred Stock [Member] Series B Convertible Preferred Stock [Member] | Convertible Preferred Stock [Member] Series C Convertible Preferred Stock [Member] | Convertible Preferred Stock [Member] Series B And C Convertible Preferred Stock [Member] | Common Stock [Member] | Common Stock [Member] Series B Convertible Preferred Stock [Member] | Common Stock [Member] Series C Convertible Preferred Stock [Member] | Common Stock [Member] Series B And C Convertible Preferred Stock [Member] | Additional Paid-in Capital [Member] | Additional Paid-in Capital [Member] Series C Convertible Preferred Stock [Member] | Accumulated Other Comprehensive Income (Loss) [Member] | Accumulated Deficit [Member]
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Balance at Dec. 31, 2017 | $ 13,000 |  |  |  |  |  |  |  |  |  | $ 413,362 |  | $ 1,387 | $ (401,749)
Balance (in shares) at Dec. 31, 2017 |  |  | 2,431 |  |  |  | 115,652 |  |  |  |  |  |  |
Share-based compensation | 143 |  |  |  |  |  |  |  |  |  | 143 |  |  |
Sale of common stock, net | 27 |  |  |  |  |  |  |  |  |  | 27 |  |  |
Sale of common stock, net (in shares) |  |  |  |  |  |  | 202 |  |  |  |  |  |  |
Conversion of Convertible Preferred Stock into common stock (share) |  |  |  | (1,228) |  |  |  | 7,375 |  |  |  |  |  |
Foreign currency translation adjustment and accumulated other comprehensive income | (281) |  |  |  |  |  |  |  |  |  |  |  | (281) |
Net loss | (4,409) |  |  |  |  |  |  |  |  |  |  |  |  | (4,409)
Balance at Mar. 31, 2018 | 8,480 |  |  |  |  |  |  |  |  |  | 413,532 |  | 1,106 | (406,158)
Balance (in shares) at Mar. 31, 2018 |  |  | 1,203 |  |  |  | 123,229 |  |  |  |  |  |  |
Balance at Dec. 31, 2017 | 13,000 |  |  |  |  |  |  |  |  |  | 413,362 |  | 1,387 | (401,749)
Balance (in shares) at Dec. 31, 2017 |  |  | 2,431 |  |  |  | 115,652 |  |  |  |  |  |  |
Net loss | (10,398) |  |  |  |  |  |  |  |  |  |  |  |  |
Balance at Sep. 30, 2018 | 6,138 |  |  |  |  |  |  |  |  |  | 417,103 |  | 1,182 | (412,147)
Balance (in shares) at Sep. 30, 2018 |  |  | 4,624 |  |  |  | 233,826 |  |  |  |  |  |  |
Balance at Mar. 31, 2018 | 8,480 |  |  |  |  |  |  |  |  |  | 413,532 |  | 1,106 | (406,158)
Balance (in shares) at Mar. 31, 2018 |  |  | 1,203 |  |  |  | 123,229 |  |  |  |  |  |  |
Share-based compensation | 96 |  |  |  |  |  |  |  |  |  | 96 |  |  |
Sale of common stock, net | (297) |  |  |  |  |  |  |  |  |  | (297) |  |  |
Sale of common stock, net (in shares) |  |  |  |  |  |  | 192 |  |  |  |  |  |  |
Conversion of Convertible Preferred Stock into common stock (share) |  |  |  | (17) |  |  |  | 103 |  |  |  |  |  |
Foreign currency translation adjustment and accumulated other comprehensive income | 131 |  |  |  |  |  |  |  |  |  |  |  | 131 |
Net loss | (3,659) |  |  |  |  |  |  |  |  |  |  |  |  | (3,659)
Balance at Jun. 30, 2018 | 4,751 |  |  |  |  |  |  |  |  |  | 413,331 |  | 1,237 | (409,817)
Balance (in shares) at Jun. 30, 2018 |  |  | 1,186 |  |  |  | 123,524 |  |  |  |  |  |  |
Share-based compensation | 86 |  |  |  |  |  |  |  |  |  | 86 |  |  |
Sale of common stock, net | 3,686 |  |  |  |  |  |  |  |  |  | 3,686 |  |  |
Sale of common stock, net (in shares) |  |  | 6,723 |  |  |  | 29,407 |  |  |  |  |  |  |
Conversion of Convertible Preferred Stock into common stock (share) |  |  |  |  |  | (3,285) |  |  |  | 80,895 |  |  |  |
Foreign currency translation adjustment and accumulated other comprehensive income | (55) |  |  |  |  |  |  |  |  |  |  |  | (55) |
Beneficial conversion feature related to Series C Convertible Preferred Stock |  | $ 2,487 |  |  |  |  |  |  |  |  |  | $ 2,487 |  |
Accretion of beneficial conversion feature related to Series C Convertible Preferred Stock |  | (2,487) |  |  |  |  |  |  |  |  |  | (2,487) |  |
Net loss | (2,330) |  |  |  |  |  |  |  |  |  |  |  |  | (2,330)
Balance at Sep. 30, 2018 | 6,138 |  |  |  |  |  |  |  |  |  | 417,103 |  | 1,182 | (412,147)
Balance (in shares) at Sep. 30, 2018 |  |  | 4,624 |  |  |  | 233,826 |  |  |  |  |  |  |
Balance at Dec. 31, 2018 | $ 5,225 |  |  |  |  |  |  |  |  |  | 418,390 |  | 1,218 | (414,383)
Balance (in shares) at Dec. 31, 2018 | 296,609 |  | 4,606 |  |  |  | 296,609 |  |  |  |  |  |  |
Share-based compensation | $ 49 |  |  |  |  |  |  |  |  |  | 49 |  |  |
Sale of common stock, net | 1,873 |  |  |  |  |  |  |  |  |  | 1,873 |  |  |
Sale of common stock, net (in shares) |  |  |  |  |  |  | 139,855 |  |  |  |  |  |  |
Conversion of Convertible Preferred Stock into common stock (share) |  |  |  |  | (66) |  |  |  | 1,653 |  |  |  |  |
Foreign currency translation adjustment and accumulated other comprehensive income | (140) |  |  |  |  |  |  |  |  |  |  |  | (140) |
Net loss | (3,150) |  |  |  |  |  |  |  |  |  |  |  |  | (3,150)
Balance at Mar. 31, 2019 | 3,857 |  |  |  |  |  |  |  |  |  | 420,312 |  | 1,078 | (417,533)
Balance (in shares) at Mar. 31, 2019 |  |  | 4,540 |  |  |  | 438,117 |  |  |  |  |  |  |
Balance at Dec. 31, 2018 | $ 5,225 |  |  |  |  |  |  |  |  |  | 418,390 |  | 1,218 | (414,383)
Balance (in shares) at Dec. 31, 2018 | 296,609 |  | 4,606 |  |  |  | 296,609 |  |  |  |  |  |  |
Exercise of warrants |  |  |  |  |  |  | 1,672,000 |  |  |  |  |  |  |
Net loss | $ (11,771) |  |  |  |  |  |  |  |  |  |  |  |  |
Balance at Sep. 30, 2019 | $ 160 |  |  |  |  |  | $ 3 |  |  |  | 426,311 |  |  | (426,154)
Balance (in shares) at Sep. 30, 2019 | 2,841,588 |  | 1,959 |  |  |  | 2,841,588 |  |  |  |  |  |  |
Balance at Mar. 31, 2019 | $ 3,857 |  |  |  |  |  |  |  |  |  | 420,312 |  | 1,078 | (417,533)
Balance (in shares) at Mar. 31, 2019 |  |  | 4,540 |  |  |  | 438,117 |  |  |  |  |  |  |
Share-based compensation | 28 |  |  |  |  |  |  |  |  |  | 28 |  |  |
Sale of common stock, net | 64 |  |  |  |  |  |  |  |  |  | 64 |  |  |
Sale of common stock, net (in shares) |  |  |  |  |  |  | 5,000 |  |  |  |  |  |  |
Foreign currency translation adjustment and accumulated other comprehensive income | (1,078) |  |  |  |  |  |  |  |  |  |  |  | $ (1,078) |
Net loss | (9,147) |  |  |  |  |  |  |  |  |  |  |  |  | (9,147)
Balance at Jun. 30, 2019 | (6,276) |  |  |  |  |  |  |  |  |  | 420,404 |  |  | (426,680)
Balance (in shares) at Jun. 30, 2019 |  |  | 4,540 |  |  |  | 443,117 |  |  |  |  |  |  |
Share-based compensation | 29 |  |  |  |  |  |  |  |  |  | 29 |  |  |
Sale of common stock and pre-funded warrants, net of offering costs | $ 4,597 |  |  |  |  |  | $ 3 |  |  |  | $ 4,594 |  |  |
Sale of common stock and pre-funded warrants, net of offering costs (in shares) |  |  |  |  |  |  | 2,000,510 |  |  |  |  |  |  |
Conversion of Convertible Preferred Stock into common stock (share) |  |  |  |  |  | (2,581) |  |  |  | 332,546 |  |  |  |
Exercise of warrants | 490 |  |  |  |  |  |  |  |  |  | 490 |  |  |
Exercise of warrants (in shares) |  |  |  |  |  |  | 65,415 |  |  |  |  |  |  |
Warrant derivative liability reclasssified to equity due to exercise of warrants | $ 794 |  |  |  |  |  |  |  |  |  | $ 794 |  |  |
Beneficial conversion feature related to Series C Convertible Preferred Stock |  | 554 |  |  |  |  |  |  |  |  |  | 554 |  |
Accretion of beneficial conversion feature related to Series C Convertible Preferred Stock |  | $ (554) |  |  |  |  |  |  |  |  |  | $ (554) |  |
Net loss | 526 |  |  |  |  |  |  |  |  |  |  |  |  | 526
Balance at Sep. 30, 2019 | $ 160 |  |  |  |  |  | $ 3 |  |  |  | $ 426,311 |  |  | $ (426,154)
Balance (in shares) at Sep. 30, 2019 | 2,841,588 |  | 1,959 |  |  |  | 2,841,588 |  |  |  |  |  |  |

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