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Price Risk Management Price Risk Management (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2014 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016
Derivative Liability, Collateral, Right to Reclaim Cash, Offset | $ 11 |  |  | $ 11 |  | $ 11
Net gain or (loss) recognized in the statement of income offset by regulatory accounting | 0 | $ (20) |  | (65) | $ (36) |
Derivative, Net Liability Position, Aggregate Fair Value | 191 |  |  | 191 |  |
Collateral Already Posted, Aggregate Fair Value | 18 |  |  | 18 |  |
Collateral cash requirement | 190 |  |  | 190 |  |
Natural Gas [Member] |  |  |  |  |  |
Derivative Instruments and Hedges, Liabilities | 3 |  |  | 3 |  | 3
4911 Electric Services [Member] |  |  |  |  |  |
Derivative Instruments and Hedges, Liabilities | 140 |  |  | 140 |  | 112
Liabilities, Total [Member] |  |  |  |  |  |
Derivative Instruments and Hedges, Liabilities | $ 143 |  |  | $ 143 |  | $ 115

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- Definition The aggregate fair value of assets that would be required to be posted as collateral for derviative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period. + References No definition available. + Details
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- Definition Net gain or loss recognized in the statement of income for derivative instruments related to price risk management activities offset by regulatory accounting. + References No definition available. + Details
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- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624258-113959 + Details
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- Definition Sum as of the balance sheet date of the (a) fair values of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and (b) the carrying amounts of the liabilities arising from financial instruments or contracts used to mitigate a specified risk (hedge), and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements. + 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 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of right to receive cash collateral under master netting arrangements offset against derivative liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 + Details
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- Definition The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624258-113959 + Details
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