Leases - Components of Lease Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Lessor, Lease, Description [Line Items]
Selling profit (charge)	$ 8	$ 8	$ 34	$ 8
Interest income	20	15	57	15
Operating lease income	21	14	$ 69	14
Sales-type Lease, Income, Comprehensive Income [Extensible List]			us-gaap:Revenues
Product revenue
Lessor, Lease, Description [Line Items]
Selling profit (charge)	26	21	$ 78	21
Cost of product
Lessor, Lease, Description [Line Items]
Selling profit (charge)	$ 18	$ 13	$ 44	$ 13