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, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator for basic per share calculation:
Income from continuing operations for basic calculation	$ 2,342,000	$ 1,508,000	$ 2,928,000	$ 1,293,000	$ 1,524,000	$ 1,130,000	$ 915,000	$ 1,047,000	$ 8,070,983	$ 4,616,385	$ 17,933,431
Income (loss) from discontinued operations, net of income tax (benefit)									2,234,000	(569,263)	(336,489)
Net income for basic calculation	3,372,000	1,644,000	4,067,000	1,222,000	1,476,000	1,080,000	822,000	669,000	10,304,983	4,047,122	17,596,942
Numerator for diluted per share calculation:
Income from continuing operations	$ 2,342,000	$ 1,508,000	$ 2,928,000	$ 1,293,000	$ 1,524,000	$ 1,130,000	$ 915,000	$ 1,047,000	8,070,983	4,616,385	17,933,431
Adjustments to income from continuing operations for the statement of operations impact of dilutive securities										(136,563)
Income from continuing operations for dilution calculation									8,070,983	4,479,822	17,933,431
Income (loss) from discontinued operations, net of income tax expense (benefit)									2,234,000	(569,263)	(336,489)
Net income for dilution calculation									$ 10,304,983	$ 3,910,559	$ 17,596,942
Denominator:
Weighted average common shares - basic	11,251,000	11,236,000	11,229,000	11,191,000	11,145,000	11,119,000	11,102,000	10,979,000	11,226,932	11,086,690	10,884,533
Effect of dilutive securities:
RSUs									142,949	169,813	242,396
Stock options									336,614	336,576	269,630
Weighted average common shares - diluted	11,744,000	11,721,000	11,690,000	11,693,000	11,688,000	11,653,000	11,531,000	11,463,000	11,706,495	11,593,079	11,396,559
Per common share amounts - basic:
Income from continuing operations	$ 0.21	$ 0.13	$ 0.26	$ 0.12	$ 0.14	$ 0.10	$ 0.08	$ 0.10	$ 0.72	$ 0.42	$ 1.65
Income (loss) from discontinued operations									0.20	(0.05)	(0.03)
Net income	0.30	0.15	0.36	0.11	0.13	0.10	0.07	0.06	0.92	0.37	1.62
Per common share amounts - diluted:
Income from continuing operations	0.20	0.13	0.25	0.11	0.12	0.10	0.08	0.09	0.69	0.39	1.57
Income (loss) from discontinued operations									0.19	(0.05)	(0.03)
Net income	$ 0.29	$ 0.14	$ 0.35	$ 0.10	$ 0.11	$ 0.09	$ 0.07	$ 0.06	$ 0.88	$ 0.34	$ 1.54