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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, 2022 | Dec. 31, 2021
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Securities Sold And Interest Receivable | $ 259 |
Total plan assets | 218,119 | $ 244,612
Large/mid-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 68,739
Small-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 16,588
International and emerging market equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 25,174
Fixed income securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 30,284 | 61,845
Private equity and hedge funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 141 | 49,017
Other assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 10,250 | 6,868
Total Plan Assets at Fair Value [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 65,330 | 195,595
Cash and Cash Equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 24,796 | 6,943
Contracts with Insurance Companies |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 9,438
Defined Benefit Plan, Common Collective Trust |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 152,389 |
Total investments measured at net asset value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 152,530 |
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 55,080 | 133,618
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 |  | 68,739
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 |  | 16,588
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 |  | 25,174
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 | 30,284 | 9,306
Quoted Prices in Active Markets for Identical Assets (Level 1) | Other assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 6,868
Quoted Prices in Active Markets for Identical Assets (Level 1) | Cash and Cash Equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 24,796 | 6,943
Quoted Prices in Active Markets for Identical Assets (Level 1) | Contracts with Insurance Companies |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 0
Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 52,539
Significant Other Observable Inputs (Level 2) | Large/mid-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 0
Significant Other Observable Inputs (Level 2) | Small-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 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 |  | 0
Significant Other Observable Inputs (Level 2) | Fixed income securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 52,539
Significant Other Observable Inputs (Level 2) | Other assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Other Observable Inputs (Level 2) | Cash and Cash Equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 0 | 0
Significant Other Observable Inputs (Level 2) | Contracts with Insurance Companies |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 0
Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | 10,250 | 9,438
Significant Unobservable Inputs (Level 3) | Large/mid-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 0
Significant Unobservable Inputs (Level 3) | Small-capitalization equity securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | 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
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 | 10,250 | 0
Significant Unobservable Inputs (Level 3) | Cash and Cash Equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value | $ 0 | 0
Significant Unobservable Inputs (Level 3) | Contracts with Insurance Companies |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Total plan assets at fair value |  | $ 9,438

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