Income Taxes - Income Tax Expense from Continuing Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Income Taxes [Line Items]
Income tax expense	$ 117,976	$ 97,494	$ 136,933	$ 50,314
Effective tax rate	40.80%	40.40%	40.20%	42.40%