Employee Benefit Plans (Defined Benefit Plan Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Assumed rates of return on invested assets	5.50%	5.50%	6.00%
Pension Benefits | Minimum
Defined Benefit Plan Disclosure [Line Items]
Discount rates — benefit obligation	3.90%	3.25%	3.60%
Discount rates — service cost	3.25%	3.60%	3.75%
Pension Benefits | Maximum
Defined Benefit Plan Disclosure [Line Items]
Discount rates — benefit obligation	4.25%	3.70%	4.20%
Discount rates — service cost	3.70%	4.20%	4.50%
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rates — benefit obligation	4.35%	3.80%	4.40%
Discount rates — service cost	3.80%	4.40%	4.75%
Salary increase assumptions	3.00%	3.00%	3.00%