Goodwill and Identifiable Intangible Assets and Liabilities - Schedule of Amortization Expense Related to Intangible Assets and Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Finite-Lived Intangible Assets and Liabilities [Line Items]
Amortization of intangible assets and liabilities	$ 175	$ 139
Retail customer relationships | Depreciation and amortization
Finite-Lived Intangible Assets and Liabilities [Line Items]
Amortization of intangible assets and liabilities	23	22
Software and other technology-related assets | Depreciation and amortization
Finite-Lived Intangible Assets and Liabilities [Line Items]
Amortization of intangible assets and liabilities	18	13
Retail and wholesale contracts | Operating revenues/Fuel, purchased power costs, and delivery fees
Finite-Lived Intangible Assets and Liabilities [Line Items]
Amortization of intangible assets and liabilities	(2)	1
Other identifiable intangible assets | Fuel, purchased power costs, and delivery fees/Depreciation and amortization
Finite-Lived Intangible Assets and Liabilities [Line Items]
Amortization of intangible assets and liabilities	$ 136	$ 103