Leases (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 60	$ 61	$ 177	$ 180
Short-term lease cost	12	15	37	45
Variable lease cost	8	10	23	20
Total lease cost	80	86	237	245
Cost of Sales [Member]
Lessee, Lease, Description [Line Items]
Total lease cost	19	21	55	59
Marketing Administration And Research Costs [Member]
Lessee, Lease, Description [Line Items]
Total lease cost	$ 61	$ 65	$ 182	$ 186