Earnings Per Common Share - Details of Computation of Earnings per Common Share, Basic and Diluted (Detail) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Numerator:
Net income for basic calculation	$ 397,643	$ 940,836	$ 932,385	$ 2,544,961
Adjustments to net income for the impact of dilutive securities	0	0	0	0
Net income for dilution calculation	$ 397,643	$ 940,836	$ 932,385	$ 2,544,961
Denominator:
Weighted average common shares - basic	11,514,123	11,321,711	11,480,900	11,302,731
Effect of dilutive securities:
RSUs	122,705	142,094	115,458	146,490
Stock options	140,189	317,066	166,447	312,989
Weighted average common shares - diluted	11,777,017	11,780,871	11,762,805	11,762,210
Basic	$ 0.03	$ 0.08	$ 0.08	$ 0.23
Diluted	$ 0.03	$ 0.08	$ 0.08	$ 0.22

Incremental common shares attributable to stock options.

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Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise stock options, restrictive stock units (RSUs), convertible preferred stock of an employee stock ownership plan (ESOP), and other dilutive convertible securities.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent, and includes adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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