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Shareholders' Equity - Weighted Average (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014 | May. 31, 2015
Stock Options |  |  |
Black-Scholes Option-Pricing model assumptions |  |  |
Expected life | 3 years 4 months 24 days | 3 years 7 months 6 days |
Expected volatility | 45.00% | 50.00% |
Dividend yield | 0.00% | 0.00% |
Risk-free interest rate | 1.20% | 1.00% |
Unrecognized compensation |  |  |
Total unrecognized compensation costs related to the outstanding stock options | $ 120,000 |  |
Total unrecognized compensation costs weighted average period of recognition | 1 year 9 months 18 days |  |
Employee Stock Purchase Plan |  |  |
Black-Scholes Option-Pricing model assumptions |  |  |
Expected life | 1 year | 1 year |
Expected volatility | 37.00% | 50.00% |
Dividend yield | 0.00% | 0.00% |
Risk-free interest rate | 0.30% | 0.10% |
Stock option disclosures |  |  |
Exercise price, expressed as percentage of fair value on date of grant | 85.00% |  |
Restricted stock units |  |  |
Unrecognized compensation |  |  |
Total unrecognized compensation costs weighted average period of recognition | 1 year 8 months 12 days |  |
Total unrecognized compensation costs related to restricted stock units | $ 149,000 |  |
2013 Plan |  |  |
Stock option disclosures |  |  |
Awards reserved for issuance | 1,100,000 |  | 1,100,000
2013 Plan | Stock Options |  |  |
Stock option disclosures |  |  |
Expiration period from date of grant | 10 years |  |
Vesting period | 3 years |  |
2013 Plan | Stock Options | Minimum |  |  |
Stock option disclosures |  |  |
Exercise price, expressed as percentage of fair value on date of grant | 100.00% |  |
2013 Plan | Restricted stock units |  |  |
Stock option disclosures |  |  |
Vesting period | 2 years 3 months 18 days | 3 years |

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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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