Segment Information - Summarized Segment Information (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Segment Reporting Information [Line Items]
Operating revenues	$ 1,323			$ 1,167			$ 3,483	$ 3,202
Depreciation and amortization	200			177			581	523
Total operating expenses, net	780			689			2,165	1,997
Interest expense	(132)			(117)			(387)	(342)
Interest income	22			23			71	52
Provision for income taxes	103			84			244	205
Net income (loss) attributable to common shareholders	350	$ 277	$ 185	323	$ 280	$ 170	812	773
Total assets	31,790			29,818			31,790	29,818	$ 30,298
Cash paid for capital expenditures	683			626			1,962	1,779
Other
Segment Reporting Information [Line Items]
Operating revenues	104			72			279	242
Depreciation and amortization	4			3			12	8
Total operating expenses, net	103			75			256	227
Interest expense	(25)			(25)			(81)	(73)
Interest income	16			16			57	38
Provision for income taxes	1			0			11	2
Net income (loss) attributable to common shareholders	(6)			(8)			(3)	(10)
Total assets	2,552			2,831			2,552	2,831
Cash paid for capital expenditures	0			7			8	14
Regulated Businesses | Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	1,219			1,095			3,204	2,960
Depreciation and amortization	196			174			569	515
Total operating expenses, net	677			614			1,909	1,770
Interest expense	(107)			(92)			(306)	(269)
Interest income	6			7			14	14
Provision for income taxes	102			84			233	203
Net income (loss) attributable to common shareholders	356			331			815	783
Total assets	29,238			26,987			29,238	26,987
Cash paid for capital expenditures	$ 683			$ 619			$ 1,954	$ 1,765