Employee Benefit Plans (Principal Assumptions In Developing Year-End Actuarial Present Value Of The Projected Benefit Obligation) (Details)	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	3.40%	3.70%
Rate of compensation increase (as a percent)	4.70%	4.60%
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	3.70%	3.90%