| Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] |
The following is a summary of stock option activity under the stock option plans for the six months ended June 30, 2016: | | | | | | | | | Weighted- | | | | | | | | | | | | | | Average | | | | | | | | | | | Weighted- | | Remaining | | Aggregate | | | | | | | | Average | | Contractual | | Intrinsic | | | | | Number of | | Exercise | | Term | | Value | | | | | Shares | | Price | | (Years) | | (in thousands) | | | Options outstanding at January 1, 2016 | | | 8,582,952 | | $ | 1.32 | | | 7.5 | | $ | 0 | | | Options granted | | | 550,000 | | $ | 0.60 | | | | | | | | | Less options forfeited | | | (280,418) | | $ | 0.66 | | | | | | | | | Less options expired/cancelled | | | (20,000) | | $ | 1.76 | | | | | | | | | Less options exercised | | | - | | $ | 0.00 | | | | | | | | | Options outstanding at June 30, 2016 | | | 8,832,534 | | $ | 1.30 | | | 7.8 | | $ | 0 | | | Options exercisable at June 30, 2016 | | | 6,181,229 | | $ | 1.39 | | | 7.3 | | $ | 0 | |
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The following is a summary of stock option activity under the stock option plans for the years ended December 31, 2015 and 2014: | | | | | | | | | Weighted- | | | | | | | | | | | | | | Average | | | | | | | | | | | Weighted- | | Remaining | | Aggregate | | | | | | | | Average | | Contractual | | Intrinsic | | | | | Number of | | Exercise | | Term | | Value | | | | | Shares | | Price | | (Years) | | (in thousands) | | | Options outstanding at December 31, 2013 | | | 6,249,952 | | $ | 1.48 | | | 8.9 | | $ | 2,605 | | | Options granted | | | 2,350,000 | | $ | 1.29 | | | | | | | | | Less options forfeited | | | (830,750) | | $ | 1.77 | | | | | | | | | Less options exercised | | | 0 | | $ | 0.00 | | | | | | | | | Options outstanding at December 31, 2014 | | | 7,769,202 | | $ | 1.40 | | | 8.5 | | $ | 255 | | | Options granted | | | 1,245,000 | | $ | 0.80 | | | | | | | | | Less options forfeited | | | (350,000) | | $ | 1.02 | | | | | | | | | Less options expired | | | (81,250) | | $ | 1.40 | | | | | | | | | Less options exercised | | | 0 | | $ | 0.00 | | | | | | | | | Options outstanding at December 31, 2015 | | | 8,582,952 | | $ | 1.32 | | | 8.2 | | $ | 0 | | | Options exercisable at December 31, 2015 | | | 5,776,716 | | $ | 1.41 | | | 7.5 | | $ | 0 | |
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| Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block] |
The following is a summary of stock options outstanding under the plans as of June 30, 2016: | | | | | | | | | | | | Stock Options | | | | | Stock Options Outstanding | | | | | Exercisable | | | | | | | | Weighted Avg. | | Weighted Avg. | | | | Weighted Avg. | | | Range of | | Number of | | Contractual Life | | Exercise | | Number of | | Exercise | | | Exercise Prices | | Shares | | (years) | | Price | | Shares | | Price | | | $ 0.01 - $ 0.71 | | | 1,078,082 | | | 9.11 | | $ | 0.61 | | | 665,582 | | $ | 0.61 | | | $ 0.80 - $ 1.00 | | | 3,062,048 | | | 7.93 | | $ | 0.93 | | | 1,478,024 | | $ | 0.96 | | | $ 1.11 - $ 1.55 | | | 1,120,000 | | | 7.74 | | $ | 1.32 | | | 842,438 | | $ | 1.25 | | | $ 1.64 - $ 2.22 | | | 3,572,404 | | | 7.30 | | $ | 1.82 | | | 3,195,185 | | $ | 1.79 | | | | | | 8,832,534 | | | 7.80 | | $ | 1.30 | | | 6,181,229 | | $ | 1.39 | |
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The following is a summary of stock options outstanding under the plans as of December 31, 2015: | | | | | | | | | | | | Stock Options | | | | | Stock Options Outstanding | | | | | Exercisable | | | | | | | | Weighted Avg. | | Weighted Avg. | | | | | Weighted Avg. | | | Range of | | Number of | | Contractual Life | | Exercise | | Number of | | Exercise | | | Exercise Prices | | Shares | | (years) | | Price | | Shares | | Price | | | $ 0.01 - $ 0.71 | | | 750,000 | | | 8.86 | | $ | 0.61 | | | 528,082 | | $ | 0.61 | | | $ 0.80 - $ 1.00 | | | 3,120,548 | | | 8.44 | | $ | 0.93 | | | 1,343,394 | | $ | 0.96 | | | $ 1.11 - $ 1.55 | | | 1,120,000 | | | 8.24 | | $ | 1.32 | | | 783,589 | | $ | 1.23 | | | $ 1.64 - $ 2.22 | | | 3,592,404 | | | 7.80 | | $ | 1.82 | | | 3,121,651 | | $ | 1.78 | | | | | | 8,582,952 | | | 8.18 | | $ | 1.32 | | | 5,776,716 | | $ | 1.41 | |
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