v2.4.0.8

Assets and Liabilities with Recurring Fair Value Measurements (Textuals) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |
Balance, beginning of period | $ 16 |  | $ 17 |  | $ 30 |
Included in net income: |  |  |  |  |  |
Included in operating revenues | 5 | [1] | 8 | [1] | 5 | [1]
Included in fuel and purchased energy expense | 0 | [2] | 0 | [2] | 0 | [2]
Included in OCI | 0 |  | 0 |  | 2 |
Purchases, issuances and settlements: |  |  |  |  |  |
Purchases | 6 |  | 3 |  | 0 |
Issuances | (2) |  | (1) |  | 0 |
Settlements | (11) |  | (11) |  | (18) |
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount | 0 |  | 0 |  | 0 |
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount | 0 |  | 0 |  | 0 |
Transfers into level 3 | 0 | [3],[4] | 0 | [3],[4] | (2) | [3],[4]
Transfers out of level 3 | 0 | [3],[5] | 0 | [3],[5] | 0 | [3],[5]
Balance, end of period | 14 |  | 16 |  | 17 |
Change in unrealized gains relating to instruments still held at end of period | 5 |  | 8 |  | 5 |
Assets and Liabilities with Recurring Fair Value Measurements (Textuals) [Abstract] |  |  |  |  |  |
Cash Equivalents Included In Cash And Cash Equivalents, Fair Value Disclosure | 889 |  | 1,274 |  |  |
Cash Equivalents Included In Restricted Cash, Fair Value Disclosure | $ 245 |  | $ 228 |  |  |
[1] | For power contracts and other power-related products, included on our Consolidated Statements of Operations.
[2] | For natural gas contracts, swaps and options, included on our Consolidated 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 during the years ended December 31, 2013, 2012 and 2011.
[4] | There were no transfers out of level 2 into level 3 for the years ended December 31, 2013 and 2012. We had $2 million in losses transferred out of level 2 into level 3 for the year ended December 31, 2011 due to changes in market liquidity in various power and natural gas markets.
[5] | We had no significant transfers out of level 3 for the years ended December 31, 2013, 2012 and 2011.

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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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