Leases (Lease Income Associated with Operating Leases) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Lessor, Lease, Description [Line Items]
Fixed payments	$ 67	$ 57	$ 56
Variable payments	131	124	128
Total lease income under operating leases	198	181	184
Operating Revenues
Lessor, Lease, Description [Line Items]
Total lease income under operating leases	103	99	121
Other Income
Lessor, Lease, Description [Line Items]
Total lease income under operating leases	$ 95	$ 82	$ 63