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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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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.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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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.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Purchase price of common stock expressed as a percentage of its fair value.

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