Goodwill - Goodwill Rollforward (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Changes in the carrying amount of goodwill
Balance of Goodwill at beginning of period		$ 2,462	$ 2,489	$ 1,893
Acquisition related adjustments			41	796
Translation effects		128	(68)	(200)
Balance of Goodwill at end of the period	$ 2,590	2,590	2,462	2,489
Impairment charge	0
Europe
Changes in the carrying amount of goodwill
Balance of Goodwill at beginning of period		808	840	926
Translation effects		105	(32)	(86)
Balance of Goodwill at end of the period	913	913	808	840
North America
Changes in the carrying amount of goodwill
Balance of Goodwill at beginning of period		1,038	1,020	723
Acquisition related adjustments			15	316
Translation effects		8	3	(19)
Balance of Goodwill at end of the period	1,046	1,046	1,038	1,020
Latin America
Changes in the carrying amount of goodwill
Balance of Goodwill at beginning of period		611	624	239
Acquisition related adjustments			26	480
Translation effects		15	(39)	(95)
Balance of Goodwill at end of the period	626	626	611	624
Other
Changes in the carrying amount of goodwill
Balance of Goodwill at beginning of period		5	5	5
Balance of Goodwill at end of the period	5	5	5	5
Asia Pacific
Changes in the carrying amount of goodwill
Balance of Goodwill at beginning of period		0	0
Balance of Goodwill at end of the period	0	0	0	0
Accumulated impairment losses	$ 1,135	$ 1,135	$ 1,135	$ 1,135