v3.19.3.a.u2

Derivative Instruments (Details) $ in Billions | 12 Months Ended
--- | ---
Dec. 31, 2019 USD ($) MMBTU MWh t | Dec. 31, 2018 USD ($) MMBTU MWh t
Power [Member] |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MWh | (184) | (161)
Natural Gas [Member] |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Energy Measure | MMBTU | (1,063) | (1,045)
Environmental Credits [Member] |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount, Mass | t | 26 | 13
Interest Rate Contract [Member] |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | $ | $ 4.8 | $ 4.5

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- Definition Nominal mass used to calculate payments on a derivative instrument. + References No definition available. + Details
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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959 + Details
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- Details
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- Details
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- Details
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- Details
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