Contingencies And Commitments (Finance Lease Expense) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Contingencies And Commitments [Abstract]
Amortization of ROU assets	$ 38,000,000	$ 53,000,000	$ 67,000,000
Interest on lease liabilities	3,000,000	6,000,000	13,000,000
Total	$ 41,000,000	$ 59,000,000	$ 80,000,000