Restructuring And Other Charges (Schedule Of Reconciliation Of The Beginning And Ending Balances Of Accrued Restructuring Charges) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
Balance at the beginning of the period			$ 1	$ 7
Costs incurred	$ 8	$ 2	12	8
Costs paid or otherwise settled			(8)	(12)
Balance at the end of the period	$ 5	$ 3	$ 5	$ 3