Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total equity at beginning of period	$ 22,640	$ 22,674	$ 23,257	$ 22,533
Total equity at end of period	22,923	22,883	22,923	22,883
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total equity at beginning of period	(480)	(37)	104	(130)
Other comprehensive income (loss)	152	88	(432)	181
Total equity at end of period	(328)	51	(328)	51
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total equity at beginning of period	(479)	(33)	104	(126)
Other comprehensive income (loss)	151	88	(432)	181
Total equity at end of period	(328)	55	(328)	55
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total equity at beginning of period	(1)	(4)	0	(4)
Other comprehensive income (loss)	0	0	(1)	0
Total equity at end of period	(1)	(4)	(1)	(4)
Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Total equity at beginning of period	0	0	0	0
Other comprehensive income (loss)	1	0	1	0
Total equity at end of period	$ 1	$ 0	$ 1	$ 0