Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($)		6 Months Ended	12 Months Ended
		Jun. 30, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, beginning		218,300
Granted, shares		13,000
Forfeited, shares		(1,195)
Exercised, shares		(24,061)
Expired, shares		(9,625)
Options outstanding and exercisable, ending		196,419	218,300
Options outstanding, beginning, Weighted Average Exercise Price		$ 6.35
Granted, Weighted Average Exercise Price		8.54
Forfeited, Weighted Average Exercise Price		8.43
Exercised, Weighted Average Exercise Price		5.69
Expired, Weighted Average Exercise Price		13.96
Options outstanding and exercisable, ending, Weighted Average Exercise Price		$ 6.20	$ 6.35
Options outstanding and exercisable, ending, Weighted Average Remaining Contractual Life		5 years 10 months 25 days	5 years 10 months 25 days
Options outstanding, ending, Aggregate Intrinsic Value	[1]	$ 629,496

[1] The aggregate intrinsic value of a stock option in the table above represents the total pre-tax intrinsic value (the amount by which the current market value of the underlying stock exceeds the exercise price of the option) that would have been received by the option holders had all option holders exercised their options on June 30, 2017. This amount changes based on changes in the market value of the Company's common stock.