Retirement Plans (Schedule Of Net Periodic Benefit Cost (Credit) For Pension And Postretirement Plans) (Details) - Pension Plan [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 1	$ 1	$ 4	$ 4
Expected return on plan assets	(2)	(3)	(6)	(9)
Amortization of net actuarial (gain) loss	1	0	1	1
Net periodic benefit cost (credit)	0	(1)	0	(2)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	$ 0	$ 1	$ 1	$ 2