Share-Based Compensation - Summary of Options Outstanding (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding, Number (in shares)	337,696
Weighted Average Remaining Contractual Life	5 years 11 months 23 days
Exercisable, Number (in shares)	186,167
Weighted Average Exercise Price (in usd per share)	$ 15.56
5.34-5.39 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, minimum (in usd per share)	$ 5.34
Range of exercise prices, maximum (in usd per share)	$ 5.39
Outstanding, Number (in shares)	37,500
Weighted Average Remaining Contractual Life	7 years 10 months 28 days
Exercisable, Number (in shares)	14,167
Weighted Average Exercise Price (in usd per share)	$ 5.38
9.07-9.56 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding, Number (in shares)	128,196
Weighted Average Remaining Contractual Life	9 years 4 months 28 days
Exercisable, Number (in shares)	0
Weighted Average Exercise Price (in usd per share)	$ 0.00
14.47 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share)	$ 14.47
Outstanding, Number (in shares)	79,500
Weighted Average Remaining Contractual Life	4 years 1 month 6 days
Exercisable, Number (in shares)	79,500
Weighted Average Exercise Price (in usd per share)	$ 14.47
15.35-16.50 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, minimum (in usd per share)	$ 15.35
Range of exercise prices, maximum (in usd per share)	$ 16.50
Outstanding, Number (in shares)	32,500
Weighted Average Remaining Contractual Life	2 years 11 months 16 days
Exercisable, Number (in shares)	32,500
Weighted Average Exercise Price (in usd per share)	$ 16.04
19.10 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share)	$ 19.10
Outstanding, Number (in shares)	30,000
Weighted Average Remaining Contractual Life	2 years 1 month 2 days
Exercisable, Number (in shares)	30,000
Weighted Average Exercise Price (in usd per share)	$ 19.10
19.17 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share)	$ 19.17
Outstanding, Number (in shares)	30,000
Weighted Average Remaining Contractual Life	1 year 1 month 2 days
Exercisable, Number (in shares)	30,000
Weighted Average Exercise Price (in usd per share)	$ 19.17