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Retirement Plans And Postretirement Benefits (Fair Asset Values Of Plan Assets) (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 107,714 | $ 136,874 |
Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 706 | 715 |
Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,023 | 910 |
Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 26,685 | 26,003 |
Fair Value Measured at Net Asset Value Per Share [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 79,300 | 109,246 |
United States |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 80,006 | 109,961 | $ 115,568
United States | Cash And Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 706 | 715 |
United States | Level 1 [Member] | Cash And Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 706 | 715 |
United States | Level 2 [Member] | Cash And Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
United States | Level 3 [Member] | Cash And Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Foreign |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27,708 | 26,913 | $ 25,082
Foreign | Foreign Government Bonds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,023 | 910 |
Foreign | Fixed Insurance Contracts [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 26,685 | 26,003 |
Foreign | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Foreign | Level 1 [Member] | Foreign Government Bonds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Foreign | Level 1 [Member] | Fixed Insurance Contracts [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Foreign | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,023 | 910 |
Foreign | Level 2 [Member] | Foreign Government Bonds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,023 | 910 |
Foreign | Level 2 [Member] | Fixed Insurance Contracts [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Foreign | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 26,685 | 26,003 |
Foreign | Level 3 [Member] | Foreign Government Bonds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Foreign | Level 3 [Member] | Fixed Insurance Contracts [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 26,685 | 26,003 |
Foreign | Fair Value, Inputs, Level 1, 2 and 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 27,708 | $ 26,913 |

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