Postretirement Plans (Schedule Of Assumptions Used To Calculate The Benefit Obligation) (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	6.80%	7.00%	7.00%
Rate of compensation increase	4.40%	4.00%	3.80%
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.00%	4.20%	3.90%
Other Postretirement Benefits Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.70%	3.80%	3.50%