Quarterly Financial Data (Schedule Of Quarterly Financial Data) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule of Quarterly Financial Information [Line Items]
Total revenues	$ 22,302	$ 20,008	$ 20,005	$ 19,383	$ 19,555	$ 17,727	$ 16,543	$ 14,910	$ 81,698	$ 68,735	$ 64,306
Total costs and expenses	(19,041)	(16,794)	(16,740)	(16,069)	(16,261)	(14,357)	(13,200)	(12,049)	(68,644)	(55,867)	(51,843)
Earnings from continuing operations	1,629	1,564	1,548	1,570	1,597	1,714	1,534	1,000	6,311	5,844	4,971
Net earnings from continuing operations	978	1,034	967	924	1,387	1,094	942	588	3,903	4,011	3,311
Net gain/(loss) on disposal of discontinued operations		(2)		(1)	6	4	(1)	(2)	(3)	7	(4)
Net earnings	$ 978	$ 1,032	$ 967	$ 923	$ 1,393	$ 1,098	$ 941	$ 586	$ 3,900	$ 4,018	$ 3,307
Basic earnings per share from continuing operations	$ 1.29	$ 1.36	$ 1.28	$ 1.23	$ 1.85	$ 1.47	$ 1.27	$ 0.79	$ 5.15	$ 5.38	$ 4.50
Basic earnings per share	$ 1.29	$ 1.36	$ 1.28	$ 1.23	$ 1.86	$ 1.47	$ 1.27	$ 0.79	$ 5.15	$ 5.39	$ 4.49
Diluted earnings per share from continuing operations	$ 1.28	$ 1.35	$ 1.27	$ 1.22	$ 1.83	$ 1.46	$ 1.25	$ 0.78	$ 5.11	$ 5.33	$ 4.46
Diluted earnings per share	$ 1.28	$ 1.35	$ 1.27	$ 1.22	$ 1.84	$ 1.46	$ 1.25	$ 0.78	$ 5.11	$ 5.34	$ 4.45
Cash dividends declared, per share	$ 0.925		$ 0.88		$ 0.86		$ 0.84		$ 1.81	$ 1.70	$ 1.68
Share Price	$ 75.36	$ 69.60	$ 74.30	$ 74.37	$ 73.35	$ 60.51	$ 73.93	$ 73.93	$ 75.36	$ 73.35
Maximum [Member]
Schedule of Quarterly Financial Information [Line Items]
Price Per Share	$ 76.56	$ 75.96	$ 77.83	$ 76.74	$ 74.74	$ 76.20	$ 80.65	$ 74.47
Minimum [Member]
Schedule of Quarterly Financial Information [Line Items]
Price Per Share	$ 69.20	$ 69.03	$ 66.82	$ 72.30	$ 56.90	$ 56.01	$ 70.29	$ 66.00