Income Tax - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Contingency [Line Items]
Excess tax benefit from exercises of share-based arrangements	$ 28,207,000	$ 8,764,000	$ 3,590,000
Income taxes, net of refunds	9,300,000	13,100,000	13,400,000
Stock Option Plan [Member]
Income Tax Contingency [Line Items]
Tax credit carry forward expiration year	2034
Excess tax benefit from exercises of share-based arrangements	28,200,000
Federal Income Tax [Member]
Income Tax Contingency [Line Items]
Net operating loss carryforwards for Federal income tax	$ 650,000