Stockholders' Equity - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended									0 Months Ended	1 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended	0 Months Ended	1 Months Ended	12 Months Ended
	Jul. 25, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Common Stock	Dec. 31, 2012 Common Stock	Dec. 31, 2013 Additional Paid-in Capital	Dec. 31, 2012 Additional Paid-in Capital	Dec. 31, 2013 Retained earnings	Dec. 31, 2012 Retained earnings	Jul. 25, 2013 Share repurchase from Third Point	Jun. 30, 2010 June 2010 Plan	Dec. 31, 2013 June 2010 Plan	May 31, 2012 May 2012 Plan	Dec. 31, 2013 May 2012 Plan	Jul. 30, 2013 May 2012 Plan Share repurchase from Third Point	Nov. 30, 2013 November 2013 Plan	Dec. 31, 2013 November 2013 Plan	Dec. 31, 2012 June 2010 and May 2012 Plan
Stockholders Equity [Line Items]
Preferred stock, shares authorized		10,000,000	10,000,000
Treasury stock acquired repurchase authorization value												$ 3,000,000,000		$ 5,000,000,000			$ 5,000,000,000
Stock repurchase program expiration date													2013-06		2015-06			2016-12
Repurchases of common stock, shares		128,863,000	126,021,000	109,716,000							40,000,000				128,863,000	40,000,000			126,021,000
Average purchase price per share of common stock repurchased during the period											$ 29.11				$ 25.95				$ 17.20
Repurchases of common stock, value											1,200,000,000				3,300,000,000				2,200,000,000
Line of Credit borrowings to fund repurchase transaction	150,000,000	150,000,000
Remaining authorized purchase capacity															93,000,000			5,000,000,000
Stock repurchased and retired		198,000,000	79,000,000
Common stock retired					198,000	79,000
Retirement of treasury stock							$ 1,600,000,000	$ 631,000,000	$ 2,900,000,000	$ 585,000,000