Shareholders' Equity (Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Balance	$ 12,287	$ 13,706	$ 12,997	$ 13,886
Net current-period other comprehensive income (loss)	65	36	(261)	(120)
Balance	12,133	13,521	12,133	13,521
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(1,122)	(824)	(857)	(714)
Other comprehensive income (loss)	55	39	(198)	(59)
Equity method affiliates	3	(1)	(9)	(13)
Net current-period other comprehensive income (loss)	58	38	(207)	(72)
Balance	(1,064)	(786)	(1,064)	(786)
Other Comprehensive Income, Tax	18	(10)	(10)	(23)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Balance	(10)	10	51	6
Other comprehensive income (loss)	17		(50)	5
Amounts reclassified from accumulated other comprehensive income (loss)	2	(2)	8	(3)
Net current-period other comprehensive income (loss)	19	(2)	(42)	2
Balance	9	$ 8	9	$ 8
Other Comprehensive Income, Tax	$ 5		$ 17