v2.4.0.6
Use of Collateral (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2012
Dec. 31, 2011
Use of Collateral [Abstract]    
Margin deposits $ 165 [1] $ 140 [1]
Natural gas and power prepayments 37 42
Total margin deposits and natural gas and power prepayments with our counterparties 202 [2] 182 [2]
Letters of credit issued 550 581
First priority liens under power and natural gas agreements 1 1
First priority liens under interest rate swap agreements 166 318
Total letters of credit and first priority liens with our counterparties 717 900
Margin deposits held by us posted by our counterparties 111 [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 112 34
Use of Collateral (Textuals) [Abstract]    
Margin And Prepayment Amounts Included In Other Assets 19 20
Margin And Prepayment Amounts Included In Margin Deposits And Other Prepaid Expenses $ 183 $ 162
[1] Balances are subject to master netting arrangements and presented on a gross basis on our Consolidated Condensed 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 March 31, 2012 and December 31, 2011, $183 million and $162 million, respectively, were included in margin deposits and other prepaid expense and $19 million and $20 million were included in other assets at March 31, 2012 and December 31, 2011, respectively, on our Consolidated Condensed Balance Sheets.
[3] Included in other current liabilities on our Consolidated Condensed Balance Sheets.