Qualified Employee Benefit Plans - The Retirement Plan's Asset Allocation Percentages (Details) - Retirement Plan	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, actual plan asset allocations, percent	100.00%	100.00%
Equity
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, actual plan asset allocations, percent	52.00%	55.00%
Debt securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, actual plan asset allocations, percent	38.00%	36.00%
Other
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, actual plan asset allocations, percent	10.00%	9.00%