Business Segments - Revenue from External Customers and Long-Lived Assets, by Geographical Areas (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	$ 16,443	$ 18,138	$ 19,540
Long-Lived Assets	6,777	7,153	7,320
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	7,338	7,558	7,820
Long-Lived Assets	2,468	2,464	2,389
Germany
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	1,905	2,288	2,372
Long-Lived Assets	778	833	891
Other international
Revenues from External Customers and Long-Lived Assets [Line Items]
Net Sales	7,200	8,292	9,348
Long-Lived Assets	2,765	3,047	3,219
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 766	$ 809	$ 821