Consolidated Statements of Comprehensive Income (Loss) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (142)us-gaap_ProfitLoss	$ 27us-gaap_ProfitLoss	$ 34us-gaap_ProfitLoss
Net cash flow hedge amounts reclassified to earnings	0	0	6
Change in fair value of cash flow hedges	0	0	(4)
Total other comprehensive income	0	0	2
Comprehensive (loss) income	(142)	27	36
Comprehensive income attributable to noncontrolling interest	15	8	2
Comprehensive (loss) income attributable to Regency Energy Partners LP	$ (157)us-gaap_ComprehensiveIncomeNetOfTax	$ 19us-gaap_ComprehensiveIncomeNetOfTax	$ 34us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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