Sales Of Receivables (Summary of Receivables Sold) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net cash received from equipment installment receivables	$ (104)	$ 1,314
Equipment Installment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net cash received from equipment installment receivables	10	1,026
Cash proceeds received	2,529	3,316
Other Sales of Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net cash received from equipment installment receivables	$ (114)	$ 288