Sale Of Equipment Installment Receivables (Finance Receivables Repurchased) (Details) - Finance Receivables [Member] - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair value of repurchased receivables		$ 288	$ 423
Carrying value of deferred purchase price		277	407
Gain (Loss) on repurchases	[1]	$ 11	$ 16

[1] These gains are included in “Selling, general and administrative” in the consolidated statements of income.