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Share-based Compensation (Details Textual) - USD ($) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Sep. 17, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Number of shares outstanding under Equity plan | 161,278 | 152,584 | 120,433 |
Stock options award, expiration | 10 years |  |  |
Weighted Average exercise Price of Options Outstanding | $ 18.30 | $ 20.20 | $ 25.72 |
Total intrinsic value of options exercised | $ 0 | $ 0 |  |
Stock-based compensation expense related to non-employees | 25,000 |  |  |
Employee Stock Option |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Unrecognized compensation expense related to unvested options | $ 307,000 |  |  |
Maturity period of weighted average period of compensation expenses | 1 year 7 months 6 days |  |  |
Restricted Stock Units (RSUs) |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Maturity period of weighted average period of compensation expenses | 1 year 9 months 18 days |  |  |
Unrecognized compensation cost related to unvested stock awards | $ 376,000 |  |  |
Minimum |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Stock options award, vesting period | 3 years |  |  |
Percentage holding for stock options exercise price | 10.00% |  |  |
Minimum | Incentive Stock Option |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Percentage of exercise price of stock option | 100.00% |  |  |
Minimum | Incentive Stock Option | Stockholders |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Percentage of exercise price of stock option | 110.00% |  |  |
Minimum | Restricted Stock Units (RSUs) |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Restricted Stock Units award, requisite service period | 3 years |  |  |
Maximum |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Stock options award, vesting period | 4 years |  |  |
Maximum | Restricted Stock Units (RSUs) |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Restricted Stock Units award, requisite service period | 4 years |  |  |
2013 Plan |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Number of shares issuable under Equity plan |  |  |  | 321,428
Number of shares outstanding under Equity plan | 210,387 |  |  |
Shares reserved for future | 64,419 |  |  |
Options and awards granted | 52,801 | 60,020 |  |
Two Thousand And Four Stock Option Plan |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Number of shares outstanding under Equity plan | 7,827 |  |  |
Weighted Average exercise Price of Options Outstanding | $ 105.24 |  |  |
Other Stock Option Plan |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |
Number of shares outstanding under Equity plan | 5,423 |  |  |
Weighted Average exercise Price of Options Outstanding | $ 131.01 |  |  |

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