Employee Benefit Plans (Defined Benefit Plan Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Assumed rates of return on invested assets	4.00%	5.50%	5.50%
Pension Benefits | Minimum
Defined Benefit Plan Disclosure [Line Items]
Discount rates — benefit obligation	1.40%	2.55%	3.90%
Discount rates — service cost	2.55%	3.90%	3.25%
Pension Benefits | Maximum
Defined Benefit Plan Disclosure [Line Items]
Discount rates — benefit obligation	2.30%	3.10%	4.25%
Discount rates — service cost	3.10%	4.25%	3.70%
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rates — benefit obligation	2.55%	3.30%	4.35%
Discount rates — service cost	3.30%	4.35%	3.80%
Salary increase assumptions	3.00%	3.00%	3.00%