Customer Financing (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Customer Financing [Line Items]
Financing Receivable, Individually Evaluated for Impairment	$ 380		$ 391
Impaired Financing Receivable, Recorded Investment	380		380
Financing Receivable, Nonaccrual	380		$ 380
Impaired Financing Receivable, Interest Income, Cash Basis Method	6	$ 8
Sales-Type and Direct Financing Leases, Lease Income	13	15
Operating Lease, Lease Income	18	31
Operating Lease, Variable Lease Income	2	1
Financing Receivable, Past Due		18
Sales-type and Direct Financing Leases, Profit (Loss)	$ 16	$ 4
CCC Credit Rating
Customer Financing [Line Items]
Percentage of Credit Default Rates Applied to Customers	25.40%
B Credit Rating
Customer Financing [Line Items]
Percentage of Credit Default Rates Applied to Customers	6.80%
BB Credit Rating
Customer Financing [Line Items]
Percentage of Credit Default Rates Applied to Customers	2.90%
BBB Credit Rating
Customer Financing [Line Items]
Percentage of Credit Default Rates Applied to Customers	0.20%