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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Employee Benefit Plans - Defined Benefit Plans Certain Information and Weighted Average Asset Allocation (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Employee benefit plans
Fair value of plan assets	$ 202,791
Mutual funds
Employee benefit plans
Fair value of plan assets	121,826
Common stock
Employee benefit plans
Fair value of plan assets	61,552
Pension Plans
Employee benefit plans
Projected benefit obligation	184,759	$ 246,934	$ 258,589
Accumulated benefit obligation	184,759	246,934
Fair value of plan assets	$ 202,791	$ 239,438	$ 216,872
Weighted average asset allocation of defined benefit plans
Total (as a percent)	100.00%	100.00%
Pension Plans \| Mutual funds
Weighted average asset allocation of defined benefit plans
Total (as a percent)	26.00%	25.00%
Pension Plans \| Common stock
Weighted average asset allocation of defined benefit plans
Total (as a percent)	65.00%	66.00%
Pension Plans \| Other
Weighted average asset allocation of defined benefit plans
Total (as a percent)	9.00%	9.00%
Minimum \| Pension Plans \| Mutual funds
Weighted average asset allocation of defined benefit plans
Target allocation, (as a percent)	20.00%	20.00%
Minimum \| Pension Plans \| Common stock
Weighted average asset allocation of defined benefit plans
Target allocation, (as a percent)	30.00%	30.00%
Minimum \| Pension Plans \| Other
Weighted average asset allocation of defined benefit plans
Target allocation, (as a percent)	5.00%	5.00%
Maximum \| Pension Plans \| Mutual funds
Weighted average asset allocation of defined benefit plans
Target allocation, (as a percent)	50.00%	50.00%
Maximum \| Pension Plans \| Common stock
Weighted average asset allocation of defined benefit plans
Target allocation, (as a percent)	60.00%	60.00%
Maximum \| Pension Plans \| Other
Weighted average asset allocation of defined benefit plans
Target allocation, (as a percent)	50.00%	50.00%