Pension and Other Postretirement Benefit Plans (Schedule of Weighted-Average Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate (as a percent)	4.34%	3.65%
Rate of compensation increase (as a percent)	3.73%	3.73%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate (as a percent)	3.69%	4.27%	4.52%
Expected long-term return on plan assets (as a percent)	6.90%	6.90%	7.25%
Expected long-term return on plan assets (as a percent)	3.73%	3.90%	3.80%
Other Postretirement Benefits
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate (as a percent)	4.34%	3.65%
Rate of compensation increase (as a percent)	0.00%	0.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate (as a percent)	3.65%	4.22%	4.50%
Expected long-term return on plan assets (as a percent)	0.00%	0.00%	0.00%
Expected long-term return on plan assets (as a percent)	0.00%	0.00%	0.00%