Environmental (Schedule of Environmental Remediation Reserves) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Environmental Remediation Obligations [Abstract]
Demerger obligations (Note 16)	$ 20	$ 22
Divestiture obligations (Note 16)	17	17
Active sites	18	18
US Superfund sites	13	13
Other environmental remediation reserves	3	2
Total	$ 71	$ 72