Acquisitions - Purchase Price Allocation (Details) - Texas Generation Portfolio $ in Millions	Apr. 10, 2025 USD ($)
Business Combination [Line Items]
Property, plant and equipment	$ 647
Other, including current and non-current working capital	(5)
Texas Generation Portfolio Purchase Price	559
Derivative, Current Assets
Business Combination [Line Items]
Derivative instruments - Current assets	6
Derivative, Other Assets
Business Combination [Line Items]
Derivative instruments - Other assets	2
Derivative, Current Liabilities
Business Combination [Line Items]
Derivative instruments - Current liabilities	(34)
Derivative, Other Liabilities
Business Combination [Line Items]
Derivative instruments - Other liabilities	$ (57)

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