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, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Numerator:
Net (loss) income for basic calculation	$ (459,003)	$ 397,643	$ (811,104)	$ 932,385
Adjustments to net (loss) income for the impact of dilutive securities	0	0	0	0
Net (loss) income for dilution calculation	$ (459,003)	$ 397,643	$ (811,104)	$ 932,385
Denominator:
Weighted average common shares - basic	11,569,692	11,514,123	11,548,723	11,480,900
Effect of dilutive securities:
RSUs		122,705		115,458
Stock options		140,189		166,447
Weighted average common shares - diluted	11,569,692	11,777,017	11,548,723	11,762,805
Net (loss) income per common share:
Basic	$ (0.04)	$ 0.03	$ (0.07)	$ 0.08
Diluted	$ (0.04)	$ 0.03	$ (0.07)	$ 0.08

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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