Property, Plant, and Equipment - Schedule of Property, Plant, and Equipment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Property, Plant and Equipment [Line Items]
Construction work in progress	$ 1,969		$ 1,969		$ 1,060
Finance lease right-of-use assets	186		186		186
Property, plant and equipment — gross	27,333		27,333		26,635
Less accumulated depreciation	(8,918)		(8,918)		(8,020)
Less finance lease right-of-use assets accumulated amortization	(39)		(39)		(33)
Property, plant and equipment — net	17,725		17,725		18,173
Impairment of long-lived and other assets	5	$ 0	73	$ 0
Texas
Property, Plant and Equipment [Line Items]
Impairment of long-lived and other assets	5		73
Power generation and structures and office and other equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment — gross	22,510		22,510		22,943
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment — gross	614		614		603
Nuclear fuel
Property, Plant and Equipment [Line Items]
Property, plant and equipment — gross	2,054		2,054		1,843
Less accumulated depreciation	$ (651)		$ (651)		$ (409)