Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Income Statement [Abstract]
Operating revenues	$ 1,276	$ 1,149	$ 2,418	$ 2,160
Operating expenses:
Operation and maintenance	480	427	948	843
Depreciation and amortization	221	193	437	381
General taxes	86	81	173	162
Other	0	(1)	0	(1)
Total operating expenses, net	787	700	1,558	1,385
Operating income	489	449	860	775
Other (expense) income:
Interest expense	(151)	(131)	(295)	(255)
Interest income	22	25	44	49
Non-operating benefit costs, net	4	7	8	16
Other, net	12	11	29	18
Total other (expense) income	(113)	(88)	(214)	(172)
Income before income taxes	376	361	646	603
Provision for income taxes	87	84	152	141
Net income attributable to common shareholders	$ 289	$ 277	$ 494	$ 462
Basic earnings per share:
Net income attributable to common shareholders (dollars per share)	$ 1.48	$ 1.42	$ 2.53	$ 2.37
Diluted earnings per share:
Net income attributable to common shareholders (dollars per share)	$ 1.48	$ 1.42	$ 2.53	$ 2.37
Weighted-average common shares outstanding:
Basic (in shares)	195	195	195	195
Diluted (in shares)	195	195	195	195