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Retirement Plans And Other Postretirement Benefits (Schedule Of Pension Plan Assets Categorized By Level Within Fair Value Measurement Hierarchy) (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Contracts with insurance companies | $ 9,899 | $ 10,495
Total plan assets | 205,367 | 226,354
Large/mid-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 37,323 | 42,920
Small-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 13,880 | 14,477
International and emerging market equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 32,931 | 34,153
Fixed income securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 17,769 | 17,513
Private equity and hedge funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 86,786 | 100,974
Other assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 6,779 | 5,822
Total Plan Assets at Fair Value [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 108,682 | 114,885
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 77,257 | 85,002
Quoted Prices in Active Markets for Identical Assets (Level 1) | Large/mid-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 37,323 | 42,920
Quoted Prices in Active Markets for Identical Assets (Level 1) | Small-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 13,880 | 14,477
Quoted Prices in Active Markets for Identical Assets (Level 1) | International and emerging market equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 13,389 | 16,409
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fixed income securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 5,886 | 5,374
Quoted Prices in Active Markets for Identical Assets (Level 1) | Other assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 6,779 | 5,822
Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 31,425 | 29,883
Significant Other Observable Inputs (Level 2) | Large/mid-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Other Observable Inputs (Level 2) | Small-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Other Observable Inputs (Level 2) | International and emerging market equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 19,542 | 17,744
Significant Other Observable Inputs (Level 2) | Fixed income securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 11,883 | 12,139
Significant Other Observable Inputs (Level 2) | Other assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Unobservable Inputs (Level 3) | Large/mid-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Unobservable Inputs (Level 3) | Small-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Unobservable Inputs (Level 3) | International and emerging market equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Unobservable Inputs (Level 3) | Fixed income securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Unobservable Inputs (Level 3) | Other assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | $ 0 | $ 0

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