Employee Benefits (Weighted-Average Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Qualified Pension Plan [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.42%	4.38%
Rate of compensation increase	3.75%	3.75%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Equivalent single discount rate for benefit obligations	4.38%	3.69%	4.18%
Equivalent single discount rate for service cost	4.44%	3.76%	4.29%
Equivalent single discount rate for interest cost	4.12%	3.42%	3.73%
Expected long-term return on plan assets	5.75%	6.75%	6.75%
Rate of compensation increase	3.75%	3.75%	3.75%
Non-Qualified Retirement Plans [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.30%	4.30%
Rate of compensation increase	3.75%	3.75%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Equivalent single discount rate for benefit obligations	4.28%	3.58%	3.96%
Equivalent single discount rate for service cost	4.48%	3.79%	4.25%
Equivalent single discount rate for interest cost	3.98%	3.22%	3.36%
Rate of compensation increase	3.75%	3.75%	3.75%