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Retirement Plans And Other Postretirement Benefits (Reconciliation Of Changes In Benefit Obligations And Plan Assets) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan Assumption Expected Long Term Return On Assets At Year End | 6.00% |  |
Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan Assumption Expected Long Term Return On Assets At Year End | 6.00% | 6.50% | 6.50%
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |
Benefit obligation, beginning of year | $ 318,123 | $ 303,126 |
Service cost | 17 | 194 | $ 231
Interest cost | 11,442 | 12,575 | 13,323
Effect of actuarial (gains) losses related to the following: |  |  |
Discount rate change | (23,653) | 21,055 |
Retirement rate assumptions and mortality table adjustments | (914) | (2,145) |
Other | (2,326) | (1,921) |
Benefits paid | 15,449 | 14,761 |
Benefit obligation, end of year | 287,240 | 318,123 | 303,126
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |
Plan assets at fair value, beginning of year | 226,354 | 214,559 |
Actual return on plan assets | (14,148) | 21,034 |
Employer contributions | 8,610 | 5,522 |
Benefits paid | 15,449 | 14,761 |
Plan assets at fair value, end of year | 205,367 | 226,354 | 214,559
Funded status of the plans | (81,873) | (91,769) |
Amounts recognized in the consolidated balance sheets: |  |  |
Net amount recognized | 81,873 | 91,769 |
Benefits paid | 15,449 | 14,761 |
Benefits paid | 15,449 | 14,761 |
Other Post-Retirement Benefits |  |  |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |
Benefit obligation, beginning of year | 7,704 | 7,436 |
Service cost | 36 | 33 | 38
Interest cost | 271 | 301 | 337
Effect of actuarial (gains) losses related to the following: |  |  |
Discount rate change | (546) | 471 |
Retirement rate assumptions and mortality table adjustments | 6 | 15 |
Other | (285) | (245) |
Plan participant contributions | 656 | 646 |
Benefits paid | 953 | 953 |
Benefit obligation, end of year | 6,889 | 7,704 | 7,436
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |
Plan assets at fair value, beginning of year | 0 | 0 |
Actual return on plan assets | 0 | 0 |
Employer contributions | 297 | 307 |
Plan participant contributions | 656 | 646 |
Benefits paid | 953 | 953 |
Plan assets at fair value, end of year | 0 | 0 | $ 0
Funded status of the plans | (6,889) | (7,704) |
Amounts recognized in the consolidated balance sheets: |  |  |
Net amount recognized | 6,889 | 7,704 |
Plan participant contributions | 656 | 646 |
Plan participant contributions | 656 | 646 |
Benefits paid | 953 | 953 |
Benefits paid | 953 | 953 |
Accrued Expenses | Pension Benefits |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |
Liability, Defined Benefit Plan, Current | 182 | 182 |
Accrued Expenses | Other Post-Retirement Benefits |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |
Liability, Defined Benefit Plan, Current | 456 | 457 |
Amounts recognized in the consolidated balance sheets: |  |  |
Liability, Defined Benefit Plan, Noncurrent | 6,433 | 7,247 |
Other Noncurrent Liabilities [Member] | Pension Benefits |  |  |
Amounts recognized in the consolidated balance sheets: |  |  |
Liability, Defined Benefit Plan, Noncurrent | $ 81,691 | $ 91,587 |

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