Segments and Geographic Information Segment and Geographic Information (Assets, Depreciation and Amortization and Capital Expenditures ) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total Assets	$ 33,112	$ 36,124	$ 36,545
Depreciation and Amortization	1,169	1,176	1,144
Capital Expenditures	2,356	2,458	2,458
Interest Income	244	245	256
Interest Expense	1,170	1,134	1,145
Investments in and Advances to Affiliates	1,197	621	610
Net Equity in Earnings of Affiliates	71	36	105
Operating Segments [Member] | US SBU
Segment Reporting Information [Line Items]
Total Assets	9,852	9,333	9,800
Depreciation and Amortization	437	471	443
Capital Expenditures	858	809	861
Interest Income	0	0	0
Interest Expense	258	236	262
Investments in and Advances to Affiliates	527	23	1
Net Equity in Earnings of Affiliates	41	9	0
Operating Segments [Member] | Andes SBU
Segment Reporting Information [Line Items]
Total Assets	8,840	8,971	8,594
Depreciation and Amortization	250	218	175
Capital Expenditures	443	538	949
Interest Income	50	57	77
Interest Expense	205	178	154
Investments in and Advances to Affiliates	358	363	345
Net Equity in Earnings of Affiliates	28	15	83
Operating Segments [Member] | Brazil SBU
Segment Reporting Information [Line Items]
Total Assets	2,034	1,516	1,179
Depreciation and Amortization	51	33	39
Capital Expenditures	34	31	47
Interest Income	45	38	31
Interest Expense	92	69	58
Operating Segments [Member] | MCAC SBU
Segment Reporting Information [Line Items]
Total Assets	5,532	5,162	4,820
Depreciation and Amortization	172	165	155
Capital Expenditures	482	480	201
Interest Income	18	11	30
Interest Expense	168	163	179
Investments in and Advances to Affiliates	3	(1)	0
Net Equity in Earnings of Affiliates	(4)	(2)	0
Operating Segments [Member] | EURASIA [Member]
Segment Reporting Information [Line Items]
Total Assets	4,557	5,777	6,200
Depreciation and Amortization	127	149	166
Capital Expenditures	211	279	131
Interest Income	130	139	116
Interest Expense	167	179	158
Investments in and Advances to Affiliates	307	236	248
Net Equity in Earnings of Affiliates	9	13	18
Segment Reconciling Items [Member] | Assets held-for-sale
Segment Reporting Information [Line Items]
Total Assets	2,034	4,936	5,411
Depreciation and Amortization	123	128	146
Capital Expenditures	315	303	252
Corporate, Non-Segment [Member] | Corporate and Other
Segment Reporting Information [Line Items]
Total Assets	263	429	541
Depreciation and Amortization	9	12	20
Capital Expenditures	13	18	17
Interest Income	1	0	2
Interest Expense	280	309	334
Investments in and Advances to Affiliates	2	0	16
Net Equity in Earnings of Affiliates	$ (3)	$ 1	$ 4