Derivatives And Hedging (Schedule Of Outstanding Derivative Instruments) (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2021 MMBTU MWh	Dec. 31, 2020 MMBTU MWh
Natural Gas [Member]
Derivative [Line Items]
Quantity \| MMBTU	46,440,000	55,630,000
Financial Transmission Rights [Member]
Derivative [Line Items]
Quantity \| MWh	7,109,024	6,922,373

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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