Postretirement Benefits (Weighted Average Assumptions Used To Determine Benefit Obligation) (Details) - Other Postretirement Benefits Plan [Member]	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.50%	4.00%
Health care cost trend rate assumed for next year	6.50%	6.50%
Rate that the cost trend rate gradually declines to	5.00%	5.00%
Year that the rate reaches the rate it is assumed to retain	2022	2022
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	9.38%	10.53%
Health care cost trend rate assumed for next year	10.27%	10.90%
Rate that the cost trend rate gradually declines to	5.15%	5.81%
Year that the rate reaches the rate it is assumed to retain	2028	2027