Other Comprehensive Earnings/Losses (Changes in Each Component of Accumulated Other Comprehensive Losses) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	$ 6,319	$ 14,789
Other comprehensive earnings (losses), net of deferred income taxes	331	(170)
Ending balance	6,637	14,081
Accumulated Other Comprehensive Losses [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	(2,864)	(2,547)
Other comprehensive earnings (losses) before reclassifications	400	(238)
Deferred income taxes	(85)	49
Other comprehensive earnings (losses) before reclassifications, net of deferred income taxes	315	(189)
Amounts reclassified to net earnings	21	27
Deferred income taxes	(5)	(8)
Amounts reclassified to net earnings, net of deferred income taxes	16	19
Other comprehensive earnings (losses), net of deferred income taxes	331	(170)
Ending balance	(2,533)	(2,717)
Benefit Plans [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	(2,192)	(2,168)
Other comprehensive earnings (losses) before reclassifications	0	0
Deferred income taxes	0	0
Other comprehensive earnings (losses) before reclassifications, net of deferred income taxes	0	0
Amounts reclassified to net earnings	28	39
Deferred income taxes	(7)	(10)
Amounts reclassified to net earnings, net of deferred income taxes	21	29
Other comprehensive earnings (losses), net of deferred income taxes	21	29
Ending balance	(2,171)	(2,139)
ABI [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	(693)	(374)
Other comprehensive earnings (losses) before reclassifications	388	(238)
Deferred income taxes	(85)	49
Other comprehensive earnings (losses) before reclassifications, net of deferred income taxes	303	(189)
Amounts reclassified to net earnings	(7)	(12)
Deferred income taxes	2	2
Amounts reclassified to net earnings, net of deferred income taxes	(5)	(10)
Other comprehensive earnings (losses), net of deferred income taxes	298	(199)
Ending balance	(395)	(573)
Currency Translation Adjustments and Other [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	21	(5)
Other comprehensive earnings (losses) before reclassifications	12	0
Deferred income taxes	0	0
Other comprehensive earnings (losses) before reclassifications, net of deferred income taxes	12	0
Amounts reclassified to net earnings	0	0
Deferred income taxes	0	0
Amounts reclassified to net earnings, net of deferred income taxes	0	0
Other comprehensive earnings (losses), net of deferred income taxes	12	0
Ending balance	$ 33	$ (5)