Employee Benefits (Schedule Of Amounts Recognized In Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plans [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain)	$ (71)	$ (53)
Total before tax	(71)	(53)
Defined Benefit Plans [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain)	9	8
Total before tax	9	8
Pension Plan Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated other comprehensive income (loss), benefits, net of tax	(43)	(30)
Other Postretirement Plan Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated other comprehensive income (loss), benefits, net of tax	0	(1)
Other Postretirement Plan Benefits [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain)	(5)	(4)
Total before tax	(5)	(4)
Other Postretirement Plan Benefits [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain)	0	0
Total before tax	$ 0	$ 0