(Components Of Postretirement Benefit Expense) (Details) - Other Postretirement Benefits Plan [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0	$ 1
Interest cost	7	8	8
Actuarial loss (gain)	5	4	9
Amortization of prior service credits	(1)	(2)	(2)
Net periodic pension expense	11	10	16
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	1	0
Interest cost	2	1	2
Actuarial loss (gain)	1	2	2
Amortization of prior service credits	(2)	(3)	(3)
Net periodic pension expense	$ 1	$ 1	$ 1