Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Significant Accounting Policies [Line Items]
Effective tax rate from continuing operations	38.00%	36.30%	38.70%	37.80%