Valuation And Qualifying Accounts (Allowance For Doubtful Accounts) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Allowance for Credit Loss
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 756	$ 1,011	$ 1,163
Charged to Costs and Expenses	1,969	1,969	1,865
Charged to Other Accounts	0	0	0
Acquisitions	0	0	0
Deductions	2,172	2,224	2,017
Balance at End of Period	553	756	1,011
Allowance for Deferred Tax Assets
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	4,656	4,175	4,343
Charged to Costs and Expenses	(318)	481	(168)
Charged to Other Accounts	0	0	0
Acquisitions	0	0	0
Deductions	0	0	0
Balance at End of Period	$ 4,338	$ 4,656	$ 4,175