v2.4.0.6

Derivative Instruments (Details) (USD $) In Millions, unless otherwise specified | Mar. 31, 2013 MMBTU MW | Dec. 31, 2012 MW MMBTU
--- | --- | ---
Price Risk Derivatives [Abstract] |  |
Power (MWh) | (16) | (16)
Natural gas (MMBtu) | 162 | 66
Interest rate swaps | $ 1,599 | $ 1,602

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- Definition Nonmonetary Notional Amount of Price Risk Derivatives Power + References No definition available. + Details
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- Definition Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Notional Amount -URI http://asc.fasb.org/extlink&oid=6519104 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 + Details
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- Details
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