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Benefit Plans (Fair values of our pension plan assets by asset category) (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair values of the Corporation's pension plan assets | $ 7,303 | $ 7,066 | $ 6,582
Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair values of the Corporation's pension plan assets | 7,303 | 7,066 |
Short-term investments [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair values of the Corporation's pension plan assets | 234 | 103 |
Short-term investments [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair values of the Corporation's pension plan assets | 234 | 103 |
Fixed income [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair values of the Corporation's pension plan assets | 3,322 | 3,273 |
Fixed income [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair values of the Corporation's pension plan assets | 3,322 | 3,273 |
Equity investments [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair values of the Corporation's pension plan assets | 3,747 | 3,690 |
Equity investments [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair values of the Corporation's pension plan assets | $ 3,747 | $ 3,690 |

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