Basis of Presentation - Changes to Allowance for Estimated Uncollectible Amounts (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Opening balance	$ 153	$ 194	$ 167	$ 215
Provisions (reversals), net	3	(21)	11	(28)
Write-offs against allowance	(6)	(4)	(33)	(20)
Recoveries and other	0	2	5	4
Closing balance	$ 150	$ 171	$ 150	$ 171