Table - FV of Partnership's Derivative Assets And Liabilities (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value Measurement, Assets	$ 85	$ 4
Fair Value Measurement, Liabilities	16us-gaap_DerivativeLiabilities	28us-gaap_DerivativeLiabilities
Embedded Derivatives in Series A Preferred Units	16	19
Embedded Derivative, Fair Value of Embedded Derivative, Net	16	19	25
Significant Observable Inputs (Level 2)
Fair Value Measurement, Assets	85	4
Fair Value Measurement, Liabilities	0	9
Embedded Derivatives in Series A Preferred Units	0	0
Unobservable Inputs (Level 3)
Fair Value Measurement, Assets	0	0
Fair Value Measurement, Liabilities	16	19
Embedded Derivatives in Series A Preferred Units		19
Natural Gas
Fair Value Measurement, Assets	26	2
Fair Value Measurement, Liabilities	0	4
Natural Gas \| Significant Observable Inputs (Level 2)
Fair Value Measurement, Assets	26	2
Fair Value Measurement, Liabilities	0	4
Natural Gas \| Unobservable Inputs (Level 3)
Fair Value Measurement, Assets	0	0
Fair Value Measurement, Liabilities	0	0
NGLs
Fair Value Measurement, Assets	23	2
Fair Value Measurement, Liabilities	0	4
NGLs \| Significant Observable Inputs (Level 2)
Fair Value Measurement, Assets	23	2
Fair Value Measurement, Liabilities	0	4
NGLs \| Unobservable Inputs (Level 3)
Fair Value Measurement, Assets	0	0
Fair Value Measurement, Liabilities	0	0
Condensate
Fair Value Measurement, Assets	36	0
Fair Value Measurement, Liabilities	0	1
Condensate \| Significant Observable Inputs (Level 2)
Fair Value Measurement, Assets	36	0
Fair Value Measurement, Liabilities	0	1
Condensate \| Unobservable Inputs (Level 3)
Fair Value Measurement, Assets	0	0
Fair Value Measurement, Liabilities	$ 0	$ 0

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

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Net fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as assets, net of those classified as liabilities.

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