Summary of Significant Accounting Policies - Details of Computation of Earnings per Common Share, Basic and Diluted (Detail) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator for basic per share calculation:
Income from continuing operations for basic calculation	$ (230,000)	$ 466,000	$ 941,000	$ 1,604,000	$ 2,342,000	$ 1,508,000	$ 2,928,000	$ 1,293,000	$ 2,780,642	$ 8,070,983	$ 4,616,385
Income (loss) from discontinued operations, net of income tax (benefit)									0	2,234,000	(569,263)
Net income for basic calculation	(230,000)	466,000	941,000	1,604,000	3,372,000	1,644,000	4,067,000	1,222,000	2,780,642	10,304,983	4,047,122
Numerator for diluted per share calculation:
Income from continuing operations	$ (230,000)	$ 466,000	$ 941,000	$ 1,604,000	$ 2,342,000	$ 1,508,000	$ 2,928,000	$ 1,293,000	2,780,642	8,070,983	4,616,385
Adjustments to income from continuing operations for the statement of operations impact of dilutive securities									0	0	(136,563)
Income from continuing operations for dilution calculation									2,780,642	8,070,983	4,479,822
Income (loss) from discontinued operations, net of income tax expense (benefit)									0	2,234,000	(569,263)
Net income for dilution calculation									$ 2,780,642	$ 10,304,983	$ 3,910,559
Denominator:
Weighted average common shares - basic	11,294,000	11,321,000	11,322,000	11,284,000	11,251,000	11,236,000	11,229,000	11,191,000	11,305,110	11,226,932	11,086,690
Effect of dilutive securities:
RSUs									138,077	142,949	169,813
Stock options									302,329	336,614	336,576
Weighted average common shares - diluted	11,294,000	11,764,000	11,781,000	11,726,000	11,744,000	11,721,000	11,690,000	11,693,000	11,745,516	11,706,495	11,593,079
Per common share amounts - basic:
Income from continuing operations	$ (0.02)	$ 0.04	$ 0.08	$ 0.14	$ 0.21	$ 0.13	$ 0.26	$ 0.12	$ 0.25	$ 0.72	$ 0.42
Income (loss) from discontinued operations									0.00	0.20	(0.05)
Net income	(0.02)	0.04	0.08	0.14	0.30	0.15	0.36	0.11	0.25	0.92	0.37
Per common share amounts - diluted:
Income from continuing operations	(0.02)	0.04	0.08	0.14	0.20	0.13	0.25	0.11	0.24	0.69	0.39
Income (loss) from discontinued operations									0.00	0.19	(0.05)
Net income	$ (0.02)	$ 0.04	$ 0.08	$ 0.14	$ 0.29	$ 0.14	$ 0.35	$ 0.10	$ 0.24	$ 0.88	$ 0.34