v2.4.0.6

Use of Collateral (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2012 | Dec. 31, 2011
--- | --- | ---
Use of Collateral [Abstract] |  |  |  |
Margin deposits | $ 196 | [1] | $ 140 | [1]
Natural gas and power prepayments | 35 |  | 42 |
Total margin deposits and natural gas and power prepayments with our counterparties | 231 | [2] | 182 | [2]
Letters of credit issued | 484 | [3] | 581 | [3]
First priority liens under power and natural gas agreements | 14 |  | 1 |
First priority liens under interest rate swap agreements | 206 |  | 318 |
Total letters of credit and first priority liens with our counterparties | 704 |  | 900 |
Margin deposits held by us posted by our counterparties | 11 | [1],[3] | 34 | [1],[3]
Letters of credit posted with us by our counterparties | 1 |  | 0 |
Total margin deposits and letters of credit posted with us by our counterparties | 12 |  | 34 |
Use of Collateral (Textuals) [Abstract] |  |  |  |
Margin And Prepayment Amounts Included In Other Assets | 20 |  | 20 |
Margin And Prepayment Amounts Included In Margin Deposits And Other Prepaid Expenses | $ 211 |  | $ 162 |
[1] | Balances are subject to master netting arrangements and presented on a gross basis on our Consolidated Balance Sheets. We do not offset fair value amounts recognized for derivative instruments executed with the same counterparty under a master netting arrangement for financial statement presentation.
[2] | At December 31, 2012 and 2011, $211 million and $162 million, respectively, were included in margin deposits and other prepaid expense and $20 million and $20 million, respectively, were included in other assets on our Consolidated Balance Sheets.
[3] | Included in other current liabilities on our Consolidated Balance Sheets.

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- Definition Derivative Collateral Right To Reclaim Cash And Natural Gas And Power Prepayments Total + References No definition available. + Details
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- Definition First priority liens under interest rate swap agreements + References No definition available. + Details
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- Definition First priority liens under power and natural gas agreements + References No definition available. + Details
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Balance Type: | debit
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- Definition Letters of credit issued + References No definition available. + Details
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Balance Type: | debit
Period Type: | instant

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- Definition Letters of Credit Issued and First Priority Liens Under Power Natural Gas And Interest Rate Swap Agreements + References No definition available. + Details
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- Definition Letters Of Credit Posted By Counterparties + References No definition available. + Details
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- Definition Margin And Prepayment Amounts Included In Margin Deposits And Other Prepaid Expenses + References No definition available. + Details
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- Definition Margin And Prepayment Amounts Included In Other Assets + References No definition available. + Details
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- Definition Natural gas and power prepayments + References No definition available. + Details
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- Details
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- Definition The amount of the obligation to return cash collateral under master netting arrangements that have not been offset against net derivative instrument positions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959 + Details
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- Definition The amount of the right to reclaim cash collateral under master netting arrangements that have not been offset against net derivative instrument positions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959 + Details
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