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v3.20.2

Accounting for Derivative Instruments and Hedging Activities - Net notional volume buy/sell of open derivative transactions (Details) shares in Millions, T in Millions, MWh in Millions, MMBTU in Millions | 6 Months Ended | 12 Months Ended
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Jun. 30, 2020 MMBTU MWh T shares | Dec. 31, 2019 MMBTU MWh T shares
Long | Emissions |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, nonmonetary notional amount, mass (ton) | T | 1 | 3
Long | Renewable Energy Certificates |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, non-monetary notional amount (in shares) | shares | 1 | 1
Long | Coal |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, nonmonetary notional amount, mass (ton) | T | 5 | 10
Long | Power |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, nonmonetary notional amount, energy measure (MMBtu/MW/Day) | MWh | (56) | (38)
Short | Natural Gas |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, nonmonetary notional amount, energy measure (MMBtu/MW/Day) | MMBTU | (237) | (181)
Short | Capacity |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, nonmonetary notional amount, energy measure (MMBtu/MW/Day) | MMBTU | (1) | (1)

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- Definition Derivative, Non-monetary Notional Amount, Other + References No definition available. + Details
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- Definition Volumetric Underlying Derivative Transactions [Abstract] + References No definition available. + Details
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- Definition Nominal energy measure used to calculate payments on a derivative instrument. + References No definition available. + Details
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- Definition Nominal mass used to calculate payments on a derivative instrument. + References No definition available. + Details
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- Details
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- Details
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- Details
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