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Pension Plans and Other Postretirement Benefits (Details-5) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 505,260 | $ 465,789
Cash and Cash Equivalents [Member] | Level 1 [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 695 | 772
Equity Securities [Member] | U.S. Large Cap [Member] | Fair Value Measured At Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 118,871 | 128,262
Equity Securities [Member] | U.S. Mid Cap [Member] | Fair Value Measured At Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 23,180 | 27,960
Equity Securities [Member] | U.S. Small Cap [Member] | Fair Value Measured At Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 32,676 | 37,222
Equity Securities [Member] | International Blend [Member] | Fair Value Measured At Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 72,948 | 73,444
Fixed Income Securities [Member] | Short-Term Fund [Member] | Fair Value Measured At Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 18,467 | 7,231
Fixed Income Securities [Member] | High Yield Bond [Member] | Fair Value Measured At Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 25,154 | 24,231
Fixed Income Securities [Member] | Long Duration Bond [Member] | Fair Value Measured At Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 185,688 | 139,631
Real Estate [Member] | Fair Value Measured At Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 27,012 | 26,146
Fixed Rate Fund [Member] | Fair Value Measured At Net Asset Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 569 | $ 890

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