Condensed Consolidated Statements Of Operations (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
REVENUES
Gas sales, including related party amounts of $22, $14, $56 and $29	$ 213	$ 141	$ 600	$ 330
NGL sales, including related party amounts of $11, $—, $23 and $24	286	267	766	709
Gathering, transportation and other fees, including related party amounts of $6, $9, $20 and $23	147	101	405	297
Net realized and unrealized (loss) gain from derivatives	(10)	1	0	20
Other	29	17	73	57
Total revenues	665	527	1,844	1,413
OPERATING COSTS AND EXPENSES
Cost of sales, including related party amounts of $8, $12, $35 and $25	477	369	1,309	959
Operation and maintenance, including related party amounts of $—, $2, $— and $21	78	61	220	159
General and administrative, including related party amounts of $2, $4, $9 and $13	13	21	64	78
(Gain) loss on asset sales, net	(1)	0	1	2
Depreciation and amortization	74	71	207	193
Total operating costs and expenses	641	522	1,801	1,391
OPERATING INCOME	24	5	43	22
Income from unconsolidated affiliates	37	21	103	87
Interest expense, net	(41)	(29)	(119)	(86)
Loss on debt refinancing, net	0	0	(7)	(8)
Other income and deductions, net	24	1	3	26
INCOME (LOSS) BEFORE INCOME TAXES	44	(2)	23	41
Income tax expense (benefit)	2	(1)	(1)	(1)
NET INCOME (LOSS)	42	(1)	24	42
Net income attributable to noncontrolling interest	(3)	(1)	(4)	(2)
NET INCOME (LOSS) ATTRIBUTABLE TO REGENCY ENERGY PARTNERS LP	39	(2)	20	40
Amounts attributable to Series A preferred units	1	2	5	7
General partner’s interest, including IDRs	3	2	8	7
Beneficial conversion feature for Class F Units	2	0	3	0
Pre-acquisition Income from SUGS Allocated to Predecessor Equity	0	0	(36)	(15)
Limited partners’ interest in net income (loss)	33	(6)	40	41
Basic and diluted net income (loss) per common unit:
Weighted average number of common units outstanding	209,559,854	170,264,621	191,334,032	166,368,178
Basic income (loss) per common unit	0.16	(0.04)	0.21	0.25
Diluted income (loss) per common unit	0.05	(0.04)	0.21	0.22
Distributions per common unit	$ 0.470	$ 0.46	$ 1.395	$ 1.38
Amount allocated to Class F units due to beneficial conversion feature	2	0	3	0
Income per Class F unit due to beneficial conversion feature	$ 0.27	$ 0.00	$ 0.45	$ 0.00
Class F Units [Member]
OPERATING COSTS AND EXPENSES
NET INCOME (LOSS)			$ 3
Basic and diluted net income (loss) per common unit:
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	6,274,483	0	6,274,483	0