Employee Benefits (Schedule Of Net Benefit Costs, Other Changes in Plan Assets and Benefit Obligation Recognized In Other Comprehensive Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Amortization of net loss	$ (2)	$ (1)	$ (3)
Defined Benefit Plan, Expected Prior Service Cost (Credit), Next Fiscal Year	0
Defined Benefit Plan, Expected Gain (Loss), Next Fiscal Year	1
Other Postretirement Plan Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Prior Service Cost (Credit), Next Fiscal Year	0
Domestic Plan [Member] | Defined Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	3	1	0
Administrative expenses	2	3	0
Interest cost	25	9	2
Expected return on plan assets	(40)	(15)	(3)
Net amortization	1	1	1
Settlement benefits	0	0	1
Net periodic benefit cost (gain)	(9)	(1)	1
Net loss (gain) emerging	(18)	(67)	1
Amortization of net loss	(1)	(1)	(2)
Total recognized in OCI	(19)	(68)	(1)
Total net periodic benefit cost and OCI	(28)	(69)	0
Domestic Plan [Member] | Other Postretirement Plan Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	0	0
Interest cost	2	1	1
Net amortization	0	0	0
Net periodic benefit cost (gain)	3	1	1
Net loss (gain) emerging	(1)	(6)	(2)
Total recognized in OCI	(1)	(6)	(2)
Total net periodic benefit cost and OCI	2	(5)	(1)
Foreign Plan [Member] | Defined Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	2	2
Administrative expenses	0	0	0
Interest cost	2	2	2
Expected return on plan assets	(1)	0	0
Net amortization	1	0	1
Settlement benefits	0	0	0
Net periodic benefit cost (gain)	4	4	5
Net loss (gain) emerging	0	13	(17)
Amortization of net loss	(1)	0	(1)
Total recognized in OCI	(1)	13	(18)
Total net periodic benefit cost and OCI	3	17	$ (13)
Foreign Plan [Member] | Other Postretirement Plan Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	0	0
Net amortization	0	0
Net periodic benefit cost (gain)	0	0
Net loss (gain) emerging	0	0
Total recognized in OCI	0	0
Total net periodic benefit cost and OCI	$ 0	$ 0