v3.19.3.a.u2
Employee Benefit Plans (Schedule of Assumptions Used) (Details)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Qualified Plan [Member] | Pension Plan [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Discount rate for benefit obligation 3.35% 4.38%  
Rate of annual compensation increase, benefit obligation 4.00% 3.75%  
Discount rate for net periodic benefit cost 4.39% 3.70% 4.34%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets 6.84% 6.84% 7.25%
Rate of annual compensation increase, net periodic benefit cost 3.75% 3.75% 3.75%
Nonqualified Plan [Member] | Supplemental Employee Retirement Plan [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Discount rate for benefit obligation 3.05% 4.18%  
Rate of annual compensation increase, benefit obligation 3.00% 3.75%  
Discount rate for net periodic benefit cost 4.18% 3.49% 3.93%
Rate of annual compensation increase, net periodic benefit cost 3.75% 3.75% 3.75%