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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
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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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