Employee Benefit Plans (Principal Assumptions In Developing Net Periodic Pension Cost) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	3.70%	4.00%
Expected return on plan assets (as a percent)	6.80%	7.10%
Rate of compensation increase (as a percent)	4.60%	4.70%
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate (as a percent)	3.90%	4.00%