Summary of Significant Accounting Policies - Minimum Volume Commitments (Details) - Minimum Volume Commitments - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Minimum Volume Commitments
Total counterparty deficiencies	$ 66	$ 33
Deferred revenue	54	17
Deficiencies not yet billed or collected	$ 12	$ 16

Amount associated with deficiencies by counterparties of their contractual minimum commitments.

No definition available.

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- Definition

Amount that has yet to be billed or collected as of the balance sheet date associated with deficiencies by counterparties of their contractual minimum commitments.

+ References

No definition available.

+ Details

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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.4(a).Q1)
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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