CONSOLIDATED STATEMENTS OF CASH FLOWS (Segment, Continuing Operations [Member], USD $) In Millions, unless otherwise specified	6 Months Ended	9 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2012 Successor [Member]	Sep. 30, 2013 Successor [Member]	Mar. 25, 2012 Predecessor [Member]	Sep. 30, 2013 SUGS [Member] Successor [Member]	Sep. 30, 2013 Missouri Gas Energy [Member] Successor [Member]	Sep. 30, 2013 ETP [Member] Successor [Member]
Cash flows from operating activities:
Net income (loss)	$ (10)	$ 134	$ 50
Adjustments to reconcile net income to net cash flows provided by operating activities:
Depreciation and amortization	155	147	57
Deferred Income Taxes	26	99	23
Provision for bad debts	6	7	1
Amortization of costs charged to interest	(17)	(25)	1
Net gain on curtailment of OPEB plans	(15)	0	0
Unrealized loss (gain) on derivatives	15	(27)	0
Non-cash compensation expense	0	5	2
Earnings from unconsolidated investments, net of cash distributions	5	0	(16)
Gain on sale of MGE, net of tax		(3)
Other Noncash Income (Expense)	0		0
Changes in operating assets and liabilities, net of merger and contribution impact	(188)	30	79
Net cash flows provided by (used in) operating activities	(23)	367	197
Cash flows from investing activities:
Proceeds from SUGS Contribution				463	973
Additions to property, plant and equipment	(138)	(193)	(60)
Loan repayment from unconsolidated investments	0	0	37
Distributions from unconsolidated affiliates in excess of cumulative earnings	0	21	0
Proceeds from Citrus Merger	0	0	1,895
Plant retirements and other	(3)	(4)	(2)
Net cash flows provided by (used in) investing activities	(141)	1,260	1,870
Cash flows from financing activities:
Issuance of long-term debt	0	0	455
Dividends paid	(65)	(313)	(19)
Note payable - related party	221	0	0			1,669
Payments on note payable - related party	(55)	0	0			(975)
Repayment of long-term debt	0	(1,795)	(1,048)
Net change in revolving credit facilities	39	(210)	12
Purchase of treasury stock	0	0	(1,453)
Other	(6)	(8)	(1)
Net cash flows provided by (used in) financing activities	134	(1,632)	(2,054)
Change in cash and cash equivalents	(30)	(5)	13
Cash and cash equivalents, beginning of period	37	49	24
Cash and cash equivalents, end of period	$ 7	$ 44	$ 37