Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Income Tax [Line Items]
Effective Income Tax Rate	35.70%	36.80%	35.50%	36.70%
Limitations on deductibility of excess annual employee compensation as mandated by health care reforms	$ 500,000		$ 500,000