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Nonqualified Benefit Plans Investments (Details 15) - Unfunded Plan - Supplemental Employee Retirement Plan - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Investments in nonqualified benefit plans	$ 143,850	$ 158,149
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Investments in nonqualified benefit plans	98,041	109,603
Life insurance carried on plan participants
Defined Benefit Plan Disclosure [Line Items]
Investments in nonqualified benefit plans	38,448	38,356
Other Investments
Defined Benefit Plan Disclosure [Line Items]
Investments in nonqualified benefit plans	$ 7,361	$ 10,190

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Investments in nonqualified benefit plans

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