CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended
	Mar. 31, 2012 Successor [Member]	Mar. 31, 2013 Successor [Member]	Mar. 25, 2012 Predecessor [Member]
Operating revenues	$ 31	$ 393	$ 443
Operating expenses:
Cost of natural gas and other energy	14	159	197
Operating, maintenance and general	61	120	116
Depreciation and amortization	4	59	49
Total operating expenses	79	338	362
Operating income	(48)	55	81
Other income (expenses):
Interest expense	(4)	(33)	(50)
Earnings from unconsolidated investments	0	1	16
Other, net	0	1	(2)
Total other expenses, net	(4)	(31)	(36)
Income from continuing operations before income tax expense	(52)	24	45
Income tax expense	(12)	10	12
Income (Loss) from Continuing Operations	(40)	14	33
Income (Loss) from Discontinued Operations	1	22	17
Net income (loss)	$ (39)	$ 36	$ 50