Fair Value Measurements (Schedule Of Valuation Process And Unobservable Inputs) (Details) - Power $ in Millions	Jun. 30, 2022 USD ($) $ / MMBTU $ / MWh	Dec. 31, 2021 USD ($) $ / MWh $ / MMBTU
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Derivative assets \| $	$ 39	$ 13
Derivative liabilities \| $	$ (119)	$ (145)
Commodity Forward Price \| Discounted cash flow \| Minimum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	36	32
Commodity Forward Price \| Discounted cash flow \| Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	122	55
Commodity Forward Price \| Discounted cash flow \| Weighted Average
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	65	40
Nodal Basis \| Discounted cash flow \| Minimum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	(17)	(14)
Nodal Basis \| Discounted cash flow \| Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	3	0
Nodal Basis \| Discounted cash flow \| Weighted Average
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	(6)	(2)
Commodity Future Price \| Discounted cash flow \| Minimum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input \| $ / MMBTU	0
Commodity Future Price \| Discounted cash flow \| Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input \| $ / MMBTU	3
Commodity Future Price \| Discounted cash flow \| Weighted Average
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input \| $ / MMBTU	2	0

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Value of input used to measure net derivative asset (liability).

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