| Net Income (Loss) Per Share   
The following table sets forth the computation of basic and diluted net income (loss) per share: 
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|   | 
Three Months Ended September 30, | 
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Nine Months Ended September 30, | 
 
|   | 
2020 | 
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2019 | 
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2020 | 
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2019 | 
 
| Numerator: | 
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| Net income (loss) applicable to common shareholders | 
$ | 
2,452  | 
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$ | 
206  | 
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$ | 
(11,849) | 
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$ | 
(9,411) | 
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| Adjustment for gain on fair value of "in the money" warrants | 
(2,545) | 
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—  | 
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(294) | 
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—  | 
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| Adjusted net income (loss) used for dilution calculation | 
$ | 
(93) | 
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$ | 
206  | 
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$ | 
(12,143) | 
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$ | 
(9,411) | 
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| Denominator: | 
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| Weighted-average number of shares outstanding | 
8,236  | 
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4,996  | 
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6,772  | 
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4,684  | 
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| Effect of dilutive shares: | 
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| "In the money" warrants for common stock | 
143  | 
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—  | 
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57  | 
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—  | 
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| Equity awards | 
—  | 
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1  | 
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—  | 
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—  | 
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| Dilutive weighted-average number of shares outstanding | 
8,379  | 
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4,997  | 
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6,829  | 
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4,684  | 
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| Net income (loss) per share applicable to common shareholders | 
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| Basic | 
$ | 
0.30  | 
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$ | 
0.04  | 
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$ | 
(1.75) | 
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$ | 
(2.01) | 
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| Diluted | 
$ | 
(0.01) | 
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$ | 
0.04  | 
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$ | 
(1.78) | 
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$ | 
(2.01) | 
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The following table sets forth potential shares of common stock that are not included in the calculation of diluted net loss per share because to do so would be anti-dilutive as of the end of each period presented: 
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|   | 
Three Months Ended September 30, | 
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Nine Months Ended September 30, | 
 
|   | 
2020 | 
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2019 | 
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2020 | 
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2019 | 
 
| Options to purchase common stock | 
532  | 
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395  | 
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532  | 
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396  | 
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| Restricted stock units | 
180  | 
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9  | 
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180  | 
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9  | 
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| Warrants for common stock | 
715  | 
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571  | 
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1,234  | 
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571  | 
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| Total common stock equivalents | 
1,427  | 
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975  | 
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1,946  | 
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976  | 
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