Schedule II (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Allowance for Bad Debts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Jan. 1		$ 122	$ 106	$ 79
Charged to costs and expenses		79	73	60
Charged to other accounts	[1]	13	26	14
Deductions from reserves	[2]	86	83	47
Balance at Dec. 31		128	122	106
NOL and Tax Credit Valuation Allowances
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Jan. 1		62	64	64
Charged to costs and expenses		26	6	5
Charged to other accounts		0	0	0
Deductions from reserves	[3]	18	8	5
Balance at Dec. 31		$ 70	$ 62	$ 64

[1] Recovery of amounts previously written-off.

[2] Deductions related primarily to bad debt write-offs.

[3] Primarily reversals of valuation allowances on completed tax credit sales and reductions of valuation allowances for items forecasted to be used prior to expiration