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Derivative Instruments and Hedging Activities - Hedged Volume of Derivative Transactions (Details) | Sep. 30, 2019 MW gal MWh MMBTU
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Electric Energy |
Derivatives, Fair Value [Line Items] |
Notional amount | MWh | 27,843,993
Capacity |
Derivatives, Fair Value [Line Items] |
Notional amount | MW | 25,054
Natural Gas |
Derivatives, Fair Value [Line Items] |
Notional amount | MMBTU | 277,395,718
Refined Fuels |
Derivatives, Fair Value [Line Items] |
Notional amount | gal | 6,720,000
CECONY | Electric Energy |
Derivatives, Fair Value [Line Items] |
Notional amount | MWh | 25,361,275
CECONY | Capacity |
Derivatives, Fair Value [Line Items] |
Notional amount | MW | 16,800
CECONY | Natural Gas |
Derivatives, Fair Value [Line Items] |
Notional amount | MMBTU | 260,350,000
CECONY | Refined Fuels |
Derivatives, Fair Value [Line Items] |
Notional amount | gal | 6,720,000

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- Definition Nominal number of units 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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