v2.4.0.8

Assets and Liabilities with Recurring Fair Value Measurements (Textuals) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Dec. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |  |  |  |
Balance, beginning of period | $ (9) |  | $ 13 |  | $ 14 |  | $ 16 |  |
Included in net income: |  |  |  |  |  |  |  |  |
Included in operating revenues | 7 | [1] | 7 | [1] | (1) | [1] | 8 | [1] |
Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included In Fuel And Purchased Energy Expense | 5 | [2] | 1 | [2] | 9 | [2] | 0 | [2] |
Purchases, issuances and settlements: |  |  |  |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases | 0 |  | 0 |  | 1 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances | 0 |  | 0 |  | 0 |  | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements | 9 |  | (5) |  | (7) |  | (8) |  |
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount | 0 |  | 0 |  | 0 |  | 0 |  |
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount | 0 |  | 0 |  | 0 |  | 0 |  |
Transfers into level 3 | 0 | [3],[4] | 0 | [3],[4] | 0 | [3],[4] | 0 | [3],[4] |
Transfers out of Level 3 | (1) | [3],[5] | 0 | [3],[5] | (5) | [3],[5] | 0 | [3],[5] |
Balance, end of period | 11 |  | 16 |  | 11 |  | 16 |  |
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) | 12 |  | 8 |  | 8 |  | 8 |  |
Assets and Liabilities with Recurring Fair Value Measurements (Textuals) [Abstract] |  |  |  |  |  |  |  |  |
Cash Equivalents Included In Cash And Cash Equivalents, Fair Value Disclosure | 1,493 |  |  |  | 1,493 |  |  |  | 889
Cash Equivalents Included In Restricted Cash, Fair Value Disclosure | $ 260 |  |  |  | $ 260 |  |  |  | $ 245
[1] | For power contracts and other power-related products, included on our Consolidated Condensed Statements of Operations.
[2] | For natural gas contracts, swaps and options, included on our Consolidated Condensed Statements of Operations.
[3] | We transfer amounts among levels of the fair value hierarchy as of the end of each period. There were no transfers into or out of level 1 for each of the three and nine months ended September 30, 2014 and 2013.
[4] | There were no transfers out of level 2 into level 3 for each of the three and nine months ended September 30, 2014 and 2013.
[5] | We had $1 million and $5 million in gains transferred out of level 3 into level 2 for the three and nine months ended September 30, 2014, respectively, primarily due to changes in market liquidity in various power markets. There were no transfers out of level 3 into level 2 for each of the three and nine months ended September 30, 2013.

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- Definition Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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