v2.4.0.8
Income Taxes - Additional Information (Detail)
3 Months Ended 9 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Sep. 30, 2013
Sep. 30, 2012
Income Tax Disclosure [Abstract]        
Effective tax rate 33.60% 34.30% 33.80% 33.30%