Other Comprehensive Earnings/Losses (Reclassifications) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net periodic benefit (income) cost, excluding service cost									$ (37)	$ (34)	$ 37
Earnings from equity investment in ABI									(1,725)	(890)	(532)
Pre-tax amounts reclassified from accumulated other comprehensive losses to net earnings (losses)	$ 1,814	$ 2,602	$ (1,997)	$ (1,121)	$ (1,251)	$ (1,944)	$ (1,877)	$ (1,895)	1,298	(6,967)	(10,227)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Earnings from equity investment in ABI									(34)	(64)	8
Pre-tax amounts reclassified from accumulated other comprehensive losses to net earnings (losses)									139	177	299
Reclassification out of Accumulated Other Comprehensive Income [Member] | Net loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net periodic benefit (income) cost, excluding service cost									200	276	325
Reclassification out of Accumulated Other Comprehensive Income [Member] | Prior service costs/credit [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net periodic benefit (income) cost, excluding service cost									(27)	(35)	(34)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Benefit Plans [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net periodic benefit (income) cost, excluding service cost									$ 173	$ 241	$ 291