Movements of Options Issued and Outstanding (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Number of Underlying Shares
Number of underlying shares, Outstanding at beginning of the period	715,000		715,000		115,000
Granted	60,000		60,000		600,000
Exercised	(110,000)		0		0
Expired	0		0		0
Forfeited	0		(60,000)		0
Number of underlying shares, Outstanding at end of the period	665,000		715,000		715,000		115,000
Number of underlying shares, Exercisable at December 31, 2013	515,000
Weighted Average Exercise Price Per Share
Weighted-Average Exercise Price Per Share, Outstanding at beginning of the period	$ 5.25		$ 5.16		$ 6.74
Granted	$ 5.60		$ 5.63		$ 4.85
Exercised	$ 4.50		$ 0		$ 0
Expired	$ 0		$ 0		$ 0
Forfeited	$ 0		$ 4.50		$ 0
Weighted-Average Exercise Price Per Share, Outstanding at end of the period	$ 5.41		$ 5.25		$ 5.16		$ 6.74
Weighted-Average Exercise Price Per Share, Exercisable at December 31, 2013	$ 5.64
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding at beginning of the period	$ 65,700	[1]	$ 213,300	[1]	$ 517,450	[1]
Granted	0	[1]	0	[1]	0	[1]
Exercised	0	[1]	0	[1]	0	[1]
Expired	0	[1]	0	[1]	0	[1]
Forfeited	0	[1]	0	[1]	0	[1]
Aggregate Intrinsic Value, Outstanding at end of the period	551,300	[1]	65,700	[1]	213,300	[1]	517,450	[1]
Aggregate Intrinsic Value, Exercisable at December 31, 2013	$ 384,800	[1]
Weighted Average Contractual Life Remaining in Years
Weighted-Average Contractual Life Remaining in Years, Outstanding	7 years 7 months 20 days		8 years 5 months 19 days		9 years 5 months 5 days		9 years
Granted	10 years		10 years		10 years
Weighted-Average Contractual Life Remaining in Years, Exercisable at December 31, 2013	7 years 6 months 14 days

[1] The intrinsic value of the stock options at December 31, 2013, 2012 and 2011 is the amount by which the market value of the Company’s common stock of $5.72, $4.39 and $4.76 as of December 31, 2013, 2012 and 2011 exceeds the exercise price of the option.