Benefit Plans (Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Plan [Member]
Weighted average assumptions used in net periodic benefit cost:
Discount rate	2.91%	3.48%	3.99%
Rate of compensation increase	4.00%	4.01%	4.04%
Long-term rate of return on assets	6.71%	6.47%	6.95%
Weighted average assumptions used in benefit obligations:
Discount rate	3.76%	3.14%
Rate of compensation increase	4.01%	3.80%
Other Postretirement Benefits Plan [Member]
Weighted average assumptions used in net periodic benefit cost:
Discount rate	3.45%	3.90%	4.30%
Weighted average assumptions used in benefit obligations:
Discount rate	4.20%	3.45%