Property, Plant and Equipment, Net - NPC (Details) - NPC - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Plant, net	$ 6,946	$ 6,921
Construction work-in-progress	703	485
Property, plant and equipment, net	7,649	7,406
Regulated
Property, Plant and Equipment [Line Items]
Generation	3,977	3,977
Distribution	1,569	1,562
Transmission	4,189	4,134
General and intangible	887	871
Utility plant in-service	10,622	10,544
Accumulated depreciation and amortization	(3,677)	(3,624)
Plant, net	$ 6,945	6,920
Regulated | Minimum
Property, Plant and Equipment [Line Items]
Useful life, generation	30 years
Useful life, distribution	45 years
Useful life, transmission	20 years
Useful life, other	5 years
Regulated | Maximum
Property, Plant and Equipment [Line Items]
Useful life, generation	55 years
Useful life, distribution	70 years
Useful life, transmission	65 years
Useful life, other	65 years
Nonregulated
Property, Plant and Equipment [Line Items]
Plant, net	$ 1	$ 1
Useful life, other	45 years