Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Other comprehensive income (loss), foreign currency transaction and translation gain (loss) arising during period, net of tax	$ 505	$ (812)	$ 330
Gains for amounts excluded from the effectiveness testing recognized in earnings	230	260
Foreign Exchange Contract [Member]
Derivative [Line Items]
Notional amount	24,100	27,400
Derivative gains to be reclassified to earnings	22
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Notional amount	11,400	14,100
Gains/(losses) from foreign currency contracts not designated as hedging instruments	(57)	405	382
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Notional amount	$ 2,800	3,200
Cash Flow Hedging [Member] | Foreign Exchange Contract [Member] | Maximum [Member]
Derivative [Line Items]
Remaining maturity	12 months
Net Investment Hedging [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Notional amount	$ 9,900	10,100
Other comprehensive income (loss), foreign currency transaction and translation gain (loss) arising during period, net of tax	$ 470	$ 521	$ (1,725)