Income Taxes - Components of Income Tax Expense (Benefit) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule Of Components Of Income Tax Expense Benefit [Line Items]
Federal - current	$ 173,061	$ 109,684	$ 183,825
State - current	267	264	191
Foreign - current	75,748	104,640	203,459
Total current	249,076	214,588	387,475
Federal - deferred	(51,852)	(1,023)	8,287
Foreign - deferred	380	3,164	(15,203)
Total deferred	(51,472)	2,141	(6,916)
Income tax expense	$ 197,604	$ 216,729	$ 380,559