Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Tax [Line Items]
Effective Income Tax Rate	37.20%	36.90%	36.00%	36.80%
Limitations on deductibility of excess annual employee compensation as mandated by health care reforms	$ 500,000		$ 500,000