CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME / (LOSS) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME / (LOSS)
Net income	$ 262us-gaap_ProfitLoss	$ 372us-gaap_ProfitLoss
Other comprehensive loss	(376)	(136)
Comprehensive income/(loss)	(114)	236
Comprehensive (income)/loss attributable to noncontrolling interests	142	(223)
Comprehensive income attributable to PAGP	$ 28us-gaap_ComprehensiveIncomeNetOfTax	$ 13us-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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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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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