Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Tax [Line Items]
Effective tax rate	37.20%	36.50%	37.20%	34.90%
Increase in uncertain tax position	$ 0