Fair Value Measurements (Schedule of Valuation Process and Unobservable Inputs) (Details) - Power $ in Millions	Dec. 31, 2023 USD ($) $ / MWh	Dec. 31, 2022 USD ($) $ / MWh $ / MMBTU
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets | $	$ 5	$ 20
Derivative Liability | $	$ (69)	$ (41)
Measurement Input, Commodity Forward Price | Minimum | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	31	38
Measurement Input, Commodity Forward Price | Maximum | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	65	89
Measurement Input, Commodity Forward Price | Weighted Average | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	43	51
Measurement Input, Nodal Basis | Minimum | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	(8)	(10)
Measurement Input, Nodal Basis | Maximum | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	(1)	(1)
Measurement Input, Nodal Basis | Weighted Average | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input	(5)	(4)
Measurement Input, Commodity Future Price | Minimum | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input		0
Measurement Input, Commodity Future Price | Maximum | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input		1
Measurement Input, Commodity Future Price | Weighted Average | Valuation Technique, Discounted Cash Flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative Asset (Liability) Net, Measurement Input | $ / MMBTU		0