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Shareholders' Equity - Price Range (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014
Options Outstanding |  |
Number Outstanding (in shares) | 895,161 |
Weighted Average Remaining Contractual Life | 7 years 22 days |
Weighted Average Exercise Price Per Share | $ 2.73 |
Options Exercisable |  |
Number Exercisable (in shares) | 653,840 | 710,598
Weighted Average Exercise Price Per Share | $ 2.66 |
Stock option disclosures |  |
Aggregate intrinsic value of options outstanding (in dollars) | $ 404,000 |
Weighted average remaining life of options exercisable | 6 years 5 months 12 days |
Aggregate intrinsic value of options exercisable (in dollars) | $ 395,000 |
Weighted average grant-date fair value of options granted (in dollars per share) | $ 0.94 | $ 1.13
Restricted stock units |  |
Number of Shares |  |
Outstanding at the beginning of the period (in shares) | 25,000 |
Granted (in shares) | 99,000 | 25,000
Vested ( in shares) | (8,334) |
Forfeited or surrendered (in shares) | (27,000) |
Outstanding at the end of the period (in shares) | 88,666 | 25,000
Weighted average grant date fair value |  |
Beginning balance fair value (per share) | $ 3.03 |
Granted (per share) | 2.71 | $ 3.03
Vested (per share) | 3.03 |
Forfeited or surrendered (per share) | 2.89 |
Ending balance fair value (per share) | 2.72 | $ 3.03
$1.61 - $2.46 |  |
Range of Exercise Prices |  |
Lower (in dollars per share) | 1.61 |
Upper (in dollars per share) | $ 2.46 |
Options Outstanding |  |
Number Outstanding (in shares) | 363,997 |
Weighted Average Remaining Contractual Life | 6 years 6 months 26 days |
Weighted Average Exercise Price Per Share | $ 1.78 |
Options Exercisable |  |
Number Exercisable (in shares) | 352,331 |
Weighted Average Exercise Price Per Share | $ 1.76 |
$2.79 - $4.22 |  |
Range of Exercise Prices |  |
Lower (in dollars per share) | 2.79 |
Upper (in dollars per share) | $ 4.22 |
Options Outstanding |  |
Number Outstanding (in shares) | 480,164 |
Weighted Average Remaining Contractual Life | 7 years 8 months 23 days |
Weighted Average Exercise Price Per Share | $ 3.16 |
Options Exercisable |  |
Number Exercisable (in shares) | 250,509 |
Weighted Average Exercise Price Per Share | $ 3.35 |
$5.49 |  |
Range of Exercise Prices |  |
Exercise price (in dollars per share) | $ 5.49 |
Options Outstanding |  |
Number Outstanding (in shares) | 51,000 |
Weighted Average Remaining Contractual Life | 4 years 4 months 28 days |
Weighted Average Exercise Price Per Share | $ 5.49 |
Options Exercisable |  |
Number Exercisable (in shares) | 51,000 |
Weighted Average Exercise Price Per Share | $ 5.49 |
2013 Plan | Board of Directors |  |
Stock option disclosures |  |
Total number of shares granted to the Board of Directors (in shares) | 37,233 | 29,701
Shares issue price (in dollars per share) | $ 2.82 | $ 3.03
Total value of shares issued | $ 105,000 | $ 90,000
2013 Plan | Restricted stock units |  |
Stock option disclosures |  |
Vesting period | 2 years 3 months 18 days | 3 years
Number of Shares |  |
Granted (in shares) | 99,000 | 25,000
Weighted average grant date fair value |  |
Granted (per share) | $ 2.71 | $ 3.03

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