Partners' Capital and Distributions (Details 8) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2011
Partners Capital and Distribution
Increase in capital from sale of PNG common units	$ 40	$ 370
PNG Common Unit Issuance
Partners Capital and Distribution
Issuance of PNG common units (in units)	1,900,000	27,600,000
Increase in capital from sale of PNG common units	8	64
Increase in noncontrolling interest from sale of PNG common units	$ 32	$ 306

Represents a sale (new stock issuance) by a subsidiary to noncontrolling interests (third parties, parties directly or indirectly unrelated to parent) during the period. The capital transaction by subsidiary does not result in a loss of control by the parent, but does effect a change in total (consolidated) equity attributable to the parent.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

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-Section 50

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-URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

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-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 55

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-URI http://asc.fasb.org/extlink&oid=31814832&loc=SL4591554-111686

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