Stock Based Compensation - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule Of Stock Option Activity [Line Items]
Allocated share-based compensation expense	$ 2,239	$ 1,788	$ 828
Compensation expense related with stock options	1,437	1,093	480
Compensation expense for stock awards	802	695	348
Total number of shares in stock based compensation plan			2,500,000
Maximum number of shares authorized to issued as options	1,361,000
Maximum number of shares issued as Options	52,000
Shares issuable upon exercise of each stock option			1
Shares issuable upon exercise of each stock Appreciation right			1.5
Term life of options	10 years
Vesting period of stock issue	3 years	3 years	3 years
Number of options, granted	354,000	285,000	216,000
Weighted average grant date fair value of the options granted	$ 5.17	$ 4.27	$ 5.98
Estimated forfeiture rate for non employee directors		0.00%
Unrecognized compensation costs to be recognized for stock options	1,151
Unrecognized compensation costs to be recognized for restricted stocks	633
Unrecognized compensation costs, period for recognition	2 years
Cash proceeds from the exercise of options	4,013	22	2,382
Total intrinsic value of options exercised	$ 1,416	$ 107	$ 1,283
Common stock issued	90,000	78,000	75,000
Weighted average grant date fair value Per Share of the Stock Award	$ 9.82
Key Employees [Member]
Schedule Of Stock Option Activity [Line Items]
Vesting period of stock issue	3 years
Non-employee Directors [Member]
Schedule Of Stock Option Activity [Line Items]
Vesting period of stock issue	1 year