Segment Reporting (Other Expenses By Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Depreciation expense	$ 787	$ 669	$ 672
Capital expenditures	1,548	1,172	960
Operating Segments [Member]
Segment Reporting Information [Line Items]
Depreciation expense	775	660	662
Capital expenditures	1,540	1,171	959
Operating Segments [Member] | European Union [Member]
Segment Reporting Information [Line Items]
Depreciation expense	213	184	184
Capital expenditures	956	665	497
Operating Segments [Member] | Eastern Europe, Middle East & Africa [Member]
Segment Reporting Information [Line Items]
Depreciation expense	164	150	163
Capital expenditures	182	223	147
Operating Segments [Member] | Asia [Member]
Segment Reporting Information [Line Items]
Depreciation expense	313	247	230
Capital expenditures	227	180	185
Operating Segments [Member] | Latin America & Canada [Member]
Segment Reporting Information [Line Items]
Depreciation expense	85	79	85
Capital expenditures	175	103	130
Other [Member]
Segment Reporting Information [Line Items]
Depreciation expense	12	9	10
Capital expenditures	$ 8	$ 1	$ 1