Accumulated Other Comprehensive Income (Loss) (Income (Expense) Effect of Reclassifications) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Affected Line Item on the Statements of Income
Interest Expense	$ (994)	$ (963)	$ (901)
Other Income (Expense) - net	309	396	(88)
Total Pre-tax	2,155	2,285	1,912
Income Taxes	(409)	(458)	(784)
Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income
Total After-Tax	(102)	(115)	(205)
Qualifying Derivatives [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income
Total Pre-tax	(18)	35	(91)
Income Taxes	5	(6)	18
Total After-Tax	(13)	29	(73)
Qualifying Derivatives [Member] | Interest Rate Swaps [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income
Interest Expense	(9)	(8)	(9)
Qualifying Derivatives [Member] | Cross Currency Swaps [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income
Interest Expense	0	1	0
Other Income (Expense) - net	(9)	42	(82)
Equity Investees AOCI [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income
Other Income (Expense) - net	0	0	(1)
Total Pre-tax	0	0	(1)
Income Taxes	0	0	0
Total After-Tax	0	0	(1)
Defined Benefit Plans [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income
Total Pre-tax	(112)	(180)	(169)
Income Taxes	23	36	38
Total After-Tax	(89)	(144)	(131)
Defined Benefit Plans [Member] | Prior Service Costs [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income
Total Pre-tax	(3)	(2)	(2)
Defined Benefit Plans [Member] | Net Actuarial Loss [Member] | Amounts Reclassified From Accumulated Other Comprehensive Income [Member]
Affected Line Item on the Statements of Income
Total Pre-tax	$ (109)	$ (178)	$ (167)