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Nonqualified Benefit Plans Investments (Details 15) - Unfunded Plan - Supplemental Employee Retirement Plan - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Defined Benefit Plan Disclosure [Line Items] |  |
Investments in nonqualified benefit plans | $ 158,149 | $ 148,800
Equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Investments in nonqualified benefit plans | 109,603 | 100,104
Life insurance carried on plan participants |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Investments in nonqualified benefit plans | 38,356 | 39,779
Other Investments |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Investments in nonqualified benefit plans | $ 10,190 | $ 8,917

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