Stockholders' Equity (Share Repurchase Program) (Narrative) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended		1 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	1 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jan. 31, 2014 January 2014 Buyback Plan [Member]	Jun. 30, 2014 January 2014 Buyback Plan [Member]	Jun. 30, 2014 Open Market Purchases [Member]	Jun. 30, 2014 Open Market Purchases [Member]	Dec. 31, 2012 December 2012 Buyback Plan [Member]	Jun. 30, 2013 December 2012 Buyback Plan [Member]
Equity, Class of Treasury Stock [Line Items]
Share buyback plan, Authorized Amount			$ 5,000				$ 1,000
Payment for the repurchase of common stock	$ 1,061	$ 1,000		$ 1,000	$ 35	$ 97		$ 1,000
Stock Repurchased and Retired During Period, Shares				15.1				20.4
Shares repurchased during period					0.5	1.5