Asset Impairment and Exit Costs (Asset Impairment and Exit Costs by Segment) (Details)	1 Months Ended		3 Months Ended		9 Months Ended
	Aug. 31, 2020 employee	Jun. 30, 2020 employee	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Restructuring Cost and Reserve [Line Items]
Total separation programs			$ 0	$ 22,000,000	$ 64,000,000	$ 40,000,000
Asset impairment charges			0	0	7,000,000	25,000,000
Asset impairment and exit costs			0	22,000,000		65,000,000
Switzerland Restructuring, Phase 1 [Member]
Restructuring Cost and Reserve [Line Items]
Expected number of positions eliminated | employee		240
Asset impairment and exit costs			0		71,000,000
Switzerland Restructuring, Phase 2 [Member]
Restructuring Cost and Reserve [Line Items]
Expected number of positions eliminated | employee	200
Asset impairment and exit costs					0
Pakistan [Member]
Restructuring Cost and Reserve [Line Items]
Asset impairment and exit costs						20,000,000
Colombia [Member]
Restructuring Cost and Reserve [Line Items]
Asset impairment and exit costs						45,000,000
European Union [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Total separation programs			0	0	24,000,000	0
Asset impairment charges			0	0	3,000,000	0
Eastern Europe [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Total separation programs			0	0	6,000,000	0
Asset impairment charges			0	0	1,000,000	0
Middle East & Africa [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Total separation programs			0	0	8,000,000	0
Asset impairment charges			0	0	1,000,000	0
South & Southeast Asia [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Total separation programs			0	0	10,000,000	3,000,000
Asset impairment charges			0	0	1,000,000	17,000,000
East Asia & Australia [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Total separation programs			0	0	12,000,000	0
Asset impairment charges			0	0	1,000,000	0
Latin America & Canada [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Total separation programs			0	22,000,000	4,000,000	37,000,000
Asset impairment charges			$ 0	$ 0	$ 0	$ 8,000,000