Inventory - Components of Inventory (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Natural gas	$ 214	$ 217
NGLs	0	23
Materials and supplies	73	67
Total inventory	$ 287	$ 307

Carrying amount as of the balance sheet date of natural gas in storage, which is a mixture of gases (liquefied or otherwise), used for fuel and manufacturing purposes, which is ready for sale.

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- Definition

Carrying amount as of the balance sheet date of liquid hydrocarbon components recovered from natural gas.

+ References

+ Details

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- References

No definition available.

+ Details

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=68049868&loc=d3e3927-108312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765

+ Details

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- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

+ Details

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