Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating leases	$ 95	$ 92
Short-term leases	2	10
Lease expense	97	102
Less: sublease income	0	0
Net lease cost	97	102
Cash payments to settle a lease liability reported in cash flows	109	104
Right-of-use assets obtained in exchange for new lease liabilities	$ 67	$ 60
Weighted average discount rate (percent)	2.51%	3.02%
Weighted average remaining lease term (in years)	5 years	5 years 1 month 6 days