Summary of Tax Positions (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Income Tax [Line Items]
Income Before Provision for Taxes	$ 1,584,913	$ 518,392	$ 566,674	$ 478,582	$ 187,167	$ 235,739	$ 135,614	$ 456,385	$ 3,148,561		$ 1,014,905		$ 77,258
Total Provision for Taxes									$ 255,642		$ 185,023		$ 345,711
Effective Income Tax Rate									8.10%	[1]	18.20%	[1]	447.50%	[1]

[1] The effective tax rate is calculated on Income (Loss) Before Provision for Taxes.