Consolidated Condensed Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Consolidated Condensed Statements of Comprehensive Income
Unrealized losses on derivatives, tax	$ 0	$ 0	$ 0	$ 1
Pension and postretirement (losses) / gains, tax	3	0	5	0
Reclassification to income of realized losses on derivatives, tax	0	0	0	(2)
Reclassification to income of realized losses on pension and postretirement, tax	$ (4)	$ 0	$ (7)	$ 0