Summary of Significant Accounting Policies - Stock Based Compensation (Details) - USD ($)	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Stock-Based Compensation:
Total stock-based compensation expense	$ 26,000	$ 83,000
Stock Options
Stock-Based Compensation:
Stock options awards (in shares)	20,000	0
Weighted average exercise price (in dollars per share)	$ 2.90
Weighted average assumptions
Expected life	2 years 6 months
Expected volatility	41.00%
Dividend yield	0.00%
Risk-free interest rate	1.00%
Options exercised (in shares)	0	23,667
Proceeds from options exercised		$ 1,000
Employee Stock Purchase Plan
Weighted average assumptions
Expected life	1 year
Expected volatility	31.00%
Dividend yield	0.00%
Risk-free interest rate	0.61%
Total fair value of stock-based rights granted	$ 3,000	$ 7,000
Restricted stock units
Stock-Based Compensation:
Restricted stock units (in shares)	0	0

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

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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