Table - Reconciliation of Total Segment Margin (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Total segment margin	$ 1,499	$ 728	$ 613
Operation and maintenance	(448)	(296)	(228)
General and administrative	(158)	(88)	(100)
(Loss) gain on asset sales, net	1	(2)	(3)
Depreciation, depletion and amortization	(541)	(287)	(252)
Goodwill, Impairment Loss	(370)	0	0
Income from unconsolidated affiliates	195	135	105
Interest expense, net	(304)	(164)	(122)
Loss on debt refinancing, net	(25)	(7)	(8)
Other income and deductions, net	12	7	29	[1]
(LOSS) INCOME BEFORE INCOME TAXES	(139)	26	34
Customer Contracts [Member]
Other income and deductions, net			$ 16

[1] *Other income and deductions, net for the year ended December 31, 2012, included a one-time producer payment of $16 million related to an assignment of certain contracts.