Selected Balance Sheet Data Balance Sheet Related Disclosures, Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions		Sep. 30, 2025	Dec. 31, 2024
Balance Sheet Related Disclosures [Abstract]
Electric plant		$ 11,973	$ 11,443
Plant to be retired	[1]	164	182
CWIP		1,014	518
Total property, plant and equipment		13,151	12,143
Less accumulated depreciation		(3,030)	(2,892)
Property, plant and equipment, net		$ 10,121	$ 9,251

[1] Amounts include Tolk Unit 1 and 2. Amounts are reported net of accumulated depreciation.