Leases (Components of Lease Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease expense	$ 47	$ 49	$ 48
Other expenses associated with operating leases 1	50	49	53
Total lease expense	97	98	101
Related cash disbursements from operating leases	50	51	$ 50
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 1	$ 9