Shareholders' Equity and Per Share Data (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			12 Months Ended					12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011 Series 1 Voting [Member]	Dec. 31, 2009 Series 1 Voting [Member]	Dec. 31, 2011 Series 2 Voting [Member]	Dec. 31, 2009 Series 2 Voting [Member]	Dec. 31, 2011 Non Voting [Member]	Dec. 31, 2011 Common Stock [Member]	Dec. 31, 2009 Common Stock [Member]	Dec. 31, 2011 Additional Paid-in Capital [Member]	Dec. 31, 2009 Additional Paid-in Capital [Member]	Dec. 31, 2011 Treasury Stock [Member]	Dec. 31, 2009 Treasury Stock [Member]
Capital Units, Authorized	6,620,000,000
Common Stock, Shares Authorized	6,500,000,000	6,500,000,000		6,000,000,000		500,000,000		100,000,000
Common Stock, Par or Stated Value Per Share	$ 2	$ 2		$ 2		$ 2		$ 0.01
Preferred Stock, Shares Authorized	20,000,000
Common Stock, Shares, Outstanding	2,996,000,000	2,988,000,000		2,996,000,000
Percent Of One Vote Per Share Common Stock	10.00%
Stock Issued During Period, Shares, Conversion of Convertible Securities				35,000,000	39,800,000	(35,000,000)	(39,800,000)
Stock Issued During Period, Value, Conversion of Convertible Securities	$ 0								$ 38	$ 80	$ 168	$ 785	$ 206	$ 865
Potentially Dilutive Shares With Average Market Price Greater Than Exercise Price	27,000,000	30,000,000	28,000,000