Summary of Significant Accounting Policies (Details 3) (USD $)	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Weighted average assumptions
Total stock-based compensation expense	$ 36,000	$ 77,000
Stock Options
Stock-Based Compensation
Awards granted	0	0
Weighted average assumptions
Total option exercises	49,670	6,666
Proceeds from option exercises	62,000	13,000
Employee stock purchase plan
Weighted average assumptions
Expected life	1 year
Expected volatility	50.00%
Dividend yield	0.00%
Risk-free interest rate	0.13%
Total fair value of stock-based rights granted	$ 10,000	$ 11,000

Represents the total fair value of option rights granted during the period.

No definition available.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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-Glossary Financing Activities

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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.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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- Definition

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

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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Number of share options (or share units) exercised during the current period.

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