Leases (Schedule of Total Lease Cost) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 40
Short-term lease cost	84	[1]
Financing lease cost:
Amortization of right-of-use assets	8
Interest on lease liabilities	10
Variable lease cost	2
Lease income	(5)
Net lease cost	$ 139

[1] Short-term lease cost excludes leases with terms of one month or less.