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v3.20.1

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 | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 MMBTU MWh T shares | Dec. 31, 2019 MWh MMBTU T shares
Short | Emissions |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, nonmonetary notional amount, mass (ton) | T | 1 | 3
Short | Natural Gas |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, nonmonetary notional amount, energy (in MMBtu and MWh) | MMBTU | 152 | 181
Short | Capacity |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, nonmonetary notional amount, energy (in MMBtu and MWh) | MMBTU | 1 | 1
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 | 7 | 10
Long | Power |  |
Volumetric Underlying Derivative Transactions |  |
Derivative, nonmonetary notional amount, energy (in MMBtu and MWh) | MWh | 46 | 38

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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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