Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Taxes [Line Items]
Effective tax rate	19.50%	27.90%	24.20%	(39.30%)
Income tax expense	$ 20,751,000	$ 24,408,000	$ 21,070,000	$ 12,505,000
Income taxes examination statute of limitations expiration date			Jul. 01, 2014
Previously unrecognized tax benefits, including interest, that will be recognized in continuing operations	$ 25,600,000		$ 25,600,000