Customer Financing (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Customer Financing [Line Items]
Financing Receivable, Individually Evaluated for Impairment	$ 402	$ 402		$ 409
Impaired Financing Receivable, Recorded Investment	391	391		398
Operative lease incentive				$ 250
Asset Impairment Charges		70	$ 44
Sales-Type and Direct Financing Leases, Lease Income	16	32
Operating Lease, Lease Income	$ 35	$ 71
B Credit Rating [Member]
Customer Financing [Line Items]
Percentage of Credit Default Rates Applied to Customers	22.10%	22.10%
BB Credit Rating [Member]
Customer Financing [Line Items]
Percentage of Credit Default Rates Applied to Customers	5.80%	5.80%
BBB Credit Rating [Member]
Customer Financing [Line Items]
Percentage of Credit Default Rates Applied to Customers	0.60%	0.60%
Lease Incentive Receivable [Member]
Customer Financing [Line Items]
Asset Impairment Charges		$ 250