Share Based Compensation (Fair Values of All Options Granted Estimated Using Binomial Option-Pricing Model with Weighted-average Assumptions) (Detail) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Disclosure Fair Values Of All Options Granted Estimated Using Binomial Option Pricing Model With Weightedaverage Assumptions [Abstract]
Dividend yield	3.04%	2.80%
Weighted average expected volatility	46.78%	53.87%
Weighted average risk-free interest rate	1.56%	0.83%
Weighted average expected lives (in years)	5 years 29 days	5 years 4 months 2 days
Weighted average grant-date fair value	$ 8.05	$ 7.99