v2.4.0.8

Assets and Liabilities with Recurring Fair Value Measurements (Textuals) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 | Dec. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |  |  |  |
Balance, beginning of period | $ 13 |  | $ 17 |  | $ 16 |  | $ 17 |  |
Included in net income: |  |  |  |  |  |  |  |  |
Included in operating revenues | 3 | [1] | (24) | [1] | 4 | [1] | (17) | [1] |
Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included In Fuel And Purchased Energy Expense | 0 | [2] | 2 | [2] | 0 | [2] | 0 | [2] |
Included in OCI | 0 |  | 0 |  | 0 |  | 4 |  |
Purchases, issuances and settlements: |  |  |  |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases | 1 |  | 1 |  | 1 |  | 1 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issues | 0 |  | (1) |  | (1) |  | (1) |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements | (3) |  | (5) |  | (5) |  | (11) |  |
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] | 0 | [3] | 0 | [3] | 0 | [3] |
Transfers out of Level 3 | 1 | [4] | 0 | [4] | 2 | [4] | 3 | [4] |
Balance, end of period | 13 |  | (10) |  | 13 |  | (10) |  |
Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Change in Unrealized Gain (Loss) Held At Period End | 3 |  | (22) |  | 4 |  | (17) |  |
Assets and Liabilities with Recurring Fair Value Measurements (Textuals) [Abstract] |  |  |  |  |  |  |  |  |
Cash Equivalents Included In Cash And Cash Equivalents, Fair Value Disclosure | 699 |  |  |  | 699 |  |  |  | 1,274
Cash Equivalents Included In Restricted Cash, Fair Value Disclosure | $ 172 |  |  |  | $ 172 |  |  |  | $ 228
[1] | For power contracts and Heat Rate swaps and options, 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] | There were no transfers out of level 2 into level 3 for each of the three and six months ended June 30, 2013 and 2012.
[4] | We had $1 million in gains transferred out of level 3 into level 2 for the three months ended June 30, 2013 and $2 million and $3 million in gains transferred out of level 3 into level 2 for the six months ended June 30, 2013 and 2012, respectively, due to changes in market liquidity in various power markets. There were no transfers out of level 3 into level 2 for the three months ended June 30, 2012.

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- Definition Amount of gain (loss) recognized in other comprehensive income (loss) for 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)(1a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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