Acquisitions - Schedule of Business Acquisitions, by Acquisitions (Details) - USD ($) $ in Millions	10 Months Ended
	Dec. 31, 2024	Mar. 01, 2024	Dec. 31, 2023
Business Acquisition [Line Items]
Goodwill	$ 2,807		$ 2,583
Business combination, contractual cash flow projections, duration	5 years
Energy Harbor
Business Acquisition [Line Items]
Cash and cash equivalents		$ 35
Trade accounts receivables, inventories, prepaid expenses, and other current assets		544
Investments		2,021
Property, plant and equipment		5,616
Identifiable intangible assets		444
Commodity and other derivative contractual assets		129
Other noncurrent assets		61
Total identifiable assets acquired		8,850
Trade accounts payable and other current liabilities		320
Long-term debt, including amounts due currently		413
Commodity and other derivative contractual liabilities		179
Accumulated deferred income taxes		1,314
Asset retirement obligations		1,368
Identifiable intangible liabilities		55
Other noncurrent liabilities and deferred credits		18
Total identifiable liabilities assumed		3,667
Identifiable net assets acquired		5,183
Goodwill		224
Net assets acquired		$ 5,407
Cash and cash equivalents	$ 5
Trade accounts receivables, inventories, prepaid expenses, and other current assets	6
Investments	0
Property, plant and equipment	(4)
Identifiable intangible assets	16
Commodity and other derivative contractual assets	(11)
Other noncurrent assets	53
Total identifiable assets acquired	65
Trade accounts payable and other current liabilities	57
Long-term debt, including amounts due currently	0
Commodity and other derivative contractual liabilities	0
Accumulated deferred income taxes	(50)
Asset retirement obligations	0
Identifiable intangible liabilities	(18)
Other noncurrent liabilities and deferred credits	6
Total identifiable liabilities assumed	(5)
Identifiable net assets acquired	70
Goodwill	$ (70)