Supplemental Data (Summary of Property, Plant and Equipment, Net) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Supplemental Data
Land	$ 164	$ 177
Buildings	2,537	2,574
Machinery and equipment	13,393	13,437
Construction in progress	453	591
Total before accumulated depreciation	16,547	16,779
Less accumulated depreciation	(9,443)	(9,420)
Total	$ 7,104	$ 7,359