Income Taxes - Components of Income Tax Expense (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Federal
Current	$ 93,345us-gaap_CurrentFederalTaxExpenseBenefit	$ 104,224us-gaap_CurrentFederalTaxExpenseBenefit	$ 86,606us-gaap_CurrentFederalTaxExpenseBenefit
Deferred	(6,023)	(19,811)	11,864
Federal income tax expense, total	87,322	84,413	98,470
State
Current	17,093	17,715	12,704
Deferred	(553)	(1,164)	(225)
State and local income tax expense, total	16,540	16,551	12,479
Foreign
Current	127,567us-gaap_CurrentForeignTaxExpenseBenefit	121,621us-gaap_CurrentForeignTaxExpenseBenefit	106,475us-gaap_CurrentForeignTaxExpenseBenefit
Deferred	0	0	0
Foreign income tax expense, total	127,567	121,621	106,475
Total
Current	238,005us-gaap_CurrentIncomeTaxExpenseBenefit	243,560us-gaap_CurrentIncomeTaxExpenseBenefit	205,785us-gaap_CurrentIncomeTaxExpenseBenefit
Deferred	(6,576)us-gaap_DeferredIncomeTaxExpenseBenefit	(20,975)us-gaap_DeferredIncomeTaxExpenseBenefit	11,639us-gaap_DeferredIncomeTaxExpenseBenefit
Income tax expense	$ 231,429us-gaap_IncomeTaxExpenseBenefit	$ 222,585us-gaap_IncomeTaxExpenseBenefit	$ 217,424us-gaap_IncomeTaxExpenseBenefit

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