10. Share-Based Employee Compensation (Details 2) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Number of options outstanding	569,500	460,500
Weighted average exercise price, outstanding	$ 4.16
Weighted average remaining contractual life (in years)	6 years 9 months 25 days
Stock options exercisable	214,800
Weighted average exercise price, exercisable	$ 4.12
Option 1
Exercise price, minimum	2.23
Exercise price, maximum	$ 3.83
Number of options outstanding	175,000
Weighted average exercise price, outstanding	$ 3.50
Weighted average remaining contractual life (in years)	7 years 8 months 5 days
Stock options exercisable	53,000
Weighted average exercise price, exercisable	$ 3.03
Option 2
Exercise price, minimum	4.07
Exercise price, maximum	$ 5.10
Number of options outstanding	394,500
Weighted average exercise price, outstanding	$ 4.45
Weighted average remaining contractual life (in years)	6 years 5 months 8 days
Stock options exercisable	161,800
Weighted average exercise price, exercisable	$ 4.48

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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