CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net loss	$ (134)	$ (216)	$ (208)	$ (221)
Net change in unrealized gains (losses), net of tax, on:
Derivatives designated as cash flow hedges	7	9	15	20
Pension and postretirement benefit plan adjustments	(2)	0	(3)	0
Other comprehensive income, net of tax	5	9	12	20
Total comprehensive income (loss)	$ (129)	$ (207)	$ (196)	$ (201)