Earnings Per Share (Schedule Of Weighted-Average Number Of Shares Outstanding Used To Compute Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Net earnings	$ 1,631	$ 2,279	$ (234)	$ 1,219	$ 1,026	$ 1,704	$ 1,110	$ 1,336	$ 4,895	$ 5,176	$ 5,446
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic									3	4	6
Net earnings available to common shareholders									$ 4,892	$ 5,172	$ 5,440
Basic weighted average shares outstanding									636.5	688.0	728.9
Participating securities									1.0	1.1	1.3
Basic weighted average common shares outstanding									635.5	686.9	727.6
Basic weighted average shares outstanding									636.5	688.0	728.9
Dilutive potential common shares									7.3	8.1	9.1
Dilutive weighted average shares outstanding									643.8	696.1	738.0
Participating securities									1.0	1.1	1.3
Diluted weighted average common shares outstanding									642.8	695.0	736.7
Income (Loss) from Continuing Operations, Per Basic Share									$ 7.70	$ 7.52	$ 7.47
Income (Loss) from Continuing Operations, Per Diluted Share									$ 7.61	$ 7.44	$ 7.38