7. Shareholders' Equity (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Repurchase of common stock, value	$ (5,307)	$ (12,346)	$ (10,468)
Weighted average exercise price of stock options granted	$ 1.06	$ 1.32	$ 1.38
Voliatility assumptions, minimum	31.00%	35.00%	44.00%
Voliatility assumptions, maximum	34.00%	37.00%	51.00%
Stock-based compensation	$ 3,515	$ 5,715	$ 5,553
Unrecognized stock-based compensation costs	$ 3,600
Weighted-average period for unrecognized costs	2 years 1 month 6 days
Intrinsic value options outstanding	$ 4,900	10,400
Intrinsic value of options exercisable	4,900	9,500
Intrinsic value of options exercised	869	$ 1,900
Proceeds from options exercised	483
Tax benefit from options exercised	$ 178
Warrants outstanding	2,000,000
Common Stock [Member]
Repurchase of common stock, shares	1,382,401
Average price per share of common stock repurchased (in dollars per share)	$ 3.81
No expiration [Member] \| Common Stock [Member]
Amount remaining of stock repurchase authorized amount	$ 7,500
2006 Plan [Member]
Shares available for grant	2,873,000

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Number of warrants or rights outstanding.

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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 options awarded to employees as compensation.

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Amount of cash inflow from issuance of shares under share-based compensation arrangement. Issuance includes, but is not limited to, exercise of stock options and similar instruments.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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The estimated measure of the maximum 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 difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount remaining of a stock repurchase plan authorized.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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