Employee Benefit Plans - Actual and Target Allocations of Plan Assets (Details)	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Actual plan asset allocations	100.00%	100.00%
Target plan asset allocations	100.00%
Common stocks [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Actual plan asset allocations	34.00%	36.00%
Target plan asset allocations	34.00%
Fixed income investments [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Actual plan asset allocations	64.00%	55.00%
Target plan asset allocations	66.00%
Real estate funds [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Actual plan asset allocations	2.00%	9.00%
Target plan asset allocations	0.00%