Hedging Activities (Summary of Notional Amounts and Respective Fair Values of Derivative Financial Instruments) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Notional amount	$ 19,230	$ 16,104
Asset derivatives, fair value	202	249
Liability derivatives, fair value	(176)	(265)
Foreign Exchange Contracts [Member] | Designated as Hedging Instrument [Member]
Notional amount	974	2,123
Foreign Exchange Contracts [Member] | Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Asset derivatives, fair value	18	38
Foreign Exchange Contracts [Member] | Designated as Hedging Instrument [Member] | Other Assets [Member]
Asset derivatives, fair value	15	37
Foreign Exchange Contracts [Member] | Designated as Hedging Instrument [Member] | Other Accrued Liabilities [Member]
Liability derivatives, fair value	(17)	(7)
Foreign Exchange Contracts [Member] | Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Liability derivatives, fair value	(7)	(4)
Foreign Exchange Contracts [Member] | Not Designated as Hedging Instrument [Member]
Notional amount	7,169	1,815
Foreign Exchange Contracts [Member] | Not Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Asset derivatives, fair value	18	5
Foreign Exchange Contracts [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Asset derivatives, fair value	14	21
Foreign Exchange Contracts [Member] | Not Designated as Hedging Instrument [Member] | Other Accrued Liabilities [Member]
Liability derivatives, fair value	(15)	(19)
Foreign Exchange Contracts [Member] | Not Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Liability derivatives, fair value	(40)
Translated Earnings Contracts [Member] | Not Designated as Hedging Instrument [Member]
Notional amount	11,087	12,166
Translated Earnings Contracts [Member] | Not Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Asset derivatives, fair value	87	114
Translated Earnings Contracts [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Asset derivatives, fair value	50	34
Translated Earnings Contracts [Member] | Not Designated as Hedging Instrument [Member] | Other Accrued Liabilities [Member]
Liability derivatives, fair value	(59)	(74)
Translated Earnings Contracts [Member] | Not Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Liability derivatives, fair value	$ (38)	$ (161)