Fair Value Measurements (Schedule Of Valuation Process And Unobservable Inputs) (Details) - Power $ in Millions	Mar. 31, 2024 USD ($) $ / MWh	Dec. 31, 2023 USD ($) $ / MWh
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Derivative Assets \| $	$ 2	$ 5
Derivative liabilities \| $	$ (54)	$ (69)
Commodity Forward Price \| Discounted cash flow \| Minimum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	22	31
Commodity Forward Price \| Discounted cash flow \| Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	68	65
Commodity Forward Price \| Discounted cash flow \| Weighted Average
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	45	43
Nodal Basis \| Discounted cash flow \| Minimum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	(8)	(8)
Nodal Basis \| Discounted cash flow \| Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	(2)	(1)
Nodal Basis \| Discounted cash flow \| Weighted Average
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Measurement input	(5)	(5)

[Line Items] for Fair Value Inputs, Assets and Liabilities, Quantitative Information [Table]

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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