Customer Financing (Schedule Of Customer Financing) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Customer Financing [Abstract]
Investment in sales-type/finance leases	$ 1,364	$ 1,482
Notes	677	807
Total financing receivables	2,041	2,289
Operating lease equipment, at cost, less accumulated depreciation of $320 and $359	1,020	1,922
Gross customer financing	3,061	4,211
Less allowance for losses on receivables	(12)	(10)	$ (16)	$ (21)
Total	3,049	4,201
Operating lease equipment, accumulated depreciation	$ 320	$ 359