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Derivative Financial Instruments - Embedded Derivatives in Commodity Contracts (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Natural Gas [Member] | Embedded derivatives in commodity contracts |  |  |
Derivative [Line Items] |  |  |
Number of Renewals |  | 2 |
Embedded Derivative Renewal Term |  | 5 years |
Embedded Derivative Fair Value of Embedded Derivative Liability Including Inception Value Allocable to Host Contract |  | $ 59 | $ 64
Not Designated as Hedging Instrument [Member] | Commodity contracts |  |  |
Derivative [Line Items] |  |  |
Derivative Liability, Fair Value, Gross Liability | [1] | 60 | 66
Not Designated as Hedging Instrument [Member] | Other Noncurrent Liabilities [Member] | Commodity contracts |  |  |
Derivative [Line Items] |  |  |
Derivative Liability, Fair Value, Gross Liability | [1] | $ 48 | $ 52
[1] | Includes embedded derivatives in commodity contracts as discussed above.

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- Definition Fair value as of the balance sheet date of a natural gas purchase agreement embedded in a gas processing agreement. The natural gas purchase agreement is an embedded derivative. This amount includes the value of the embedded purchase agreement at the inception of the arrangement. however, in accordance with GAAP, the fair value of the embedded derivative at inception is deemed to be allocable to the host contract and is not separately recorded as an embedded derivative. + References No definition available. + Details
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- Definition Represents the term for which the counterparty has the option to renew a purchase agreement related to an embedded derivative. + References No definition available. + Details
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- Definition Number of Times for Automatic Renewal + References No definition available. + Details
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- Definition Fair value, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4D -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313 + 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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- Details
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- Details
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