Stockholders' Equity - Additional Information (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	1 Months Ended	3 Months Ended	12 Months Ended			36 Months Ended	69 Months Ended			18 Months Ended	1 Months Ended
	Feb. 27, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2015	Dec. 31, 2013	Dec. 31, 2008	Nov. 30, 2006	Jun. 30, 2014 Scenario, Forecast	Nov. 30, 2006 Sold Warrants
Sold warrants to acquire shares of our common stock											215
Sold warrants to acquire shares of our common stock, exercise price per share									19.55
Common stock excluded from calculation of diluted earnings per share			4	4	13
Number of shares authorized for issuance		500	500				500	250
Total Repurchases of Common Stock, shares			122				345
Total Repurchases of Common Stock			$ 3,000,000,000				$ 7,400,000,000
Common stock, shares reserved for future issuance		155	155				155
Plan to spend for the year on common stock repurchases						$ 6,000,000,000				$ 3,500,000,000
Additional number of shares authorized for issuance	250
Cash dividends declared per common share		$ 0.10	$ 0.30	$ 0	$ 0
Common Stock, Dividends, Per Share, Cash Paid		$ 202,000,000	$ 415,000,000