Federal and Foreign Income Tax - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Income before federal and foreign income taxes from U.S operations	$ 2,766	$ 1,373	$ 1,666
Income before federal and foreign income taxes from foreign operations	471	623	533
Deferred income tax asset valuation allowance	$ 13	$ 12