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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
--- | --- | ---
Feb. 09, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Pension Benefits |  |  |  |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |
Benefit obligation, beginning of year |  | $ 316,169 | $ 336,159 |
Service cost |  | 0 | 0 | $ 0
Interest cost |  | 8,945 | 8,398 | 10,156
Effect of actuarial (gains) losses related to the following: |  |  |  |
Discount rate change |  | (61,519) | (12,512) |
Retirement rate assumptions and mortality table adjustments |  |  | 1,028 |
Other |  | 1,513 | (101) |
Plan participant contributions |  | 0 | 0 |
Benefits paid |  | 16,994 | 16,803 |
Benefit obligation, end of year |  | 248,114 | 316,169 | 336,159
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |
Plan assets at fair value, beginning of year |  | 244,612 | 233,075 |
Actual return on plan assets |  | (59,683) | 23,131 |
Employer contributions | $ 50,000 | 50,184 | 5,209 |
Plan participant contributions |  | 0 | 0 |
Benefits paid |  | 16,994 | 16,803 |
Plan assets at fair value, end of year |  | 218,119 | 244,612 | 233,075
Funded status of the plans |  | (29,995) | (71,557) |
Amounts recognized in the consolidated balance sheets: |  |  |  |
Net amount recognized |  | 29,995 | 71,557 |
Other Post-Retirement Benefits |  |  |  |
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] |  |  |  |
Benefit obligation, beginning of year |  | 7,370 | 8,164 |
Service cost |  | 18 | 21 | 29
Interest cost |  | 207 | 195 | 243
Effect of actuarial (gains) losses related to the following: |  |  |  |
Discount rate change |  | (1,483) | (272) |
Retirement rate assumptions and mortality table adjustments |  |  | (1) |
Other |  | 90 | (274) |
Plan participant contributions |  | 554 | 613 |
Benefits paid |  | 1,030 | 1,076 |
Benefit obligation, end of year |  | 5,726 | 7,370 | 8,164
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 |  | 476 | 463 |
Plan participant contributions |  | 554 | 613 |
Benefits paid |  | 1,030 | 1,076 |
Plan assets at fair value, end of year |  | 0 | 0 | $ 0
Funded status of the plans |  | (5,726) | (7,370) |
Amounts recognized in the consolidated balance sheets: |  |  |  |
Net amount recognized |  | 5,726 | 7,370 |
Accrued Expenses | Pension Benefits |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |
Liability, Defined Benefit Plan, Current |  | 180 | 181 |
Accrued Expenses | Other Post-Retirement Benefits |  |  |  |
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] |  |  |  |
Liability, Defined Benefit Plan, Current |  | 489 | 478 |
Other Noncurrent Liabilities [Member] | Pension Benefits |  |  |  |
Amounts recognized in the consolidated balance sheets: |  |  |  |
Liability, Defined Benefit Plan, Noncurrent |  | 29,815 | 71,376 |
Other Noncurrent Liabilities [Member] | Other Post-Retirement Benefits |  |  |  |
Amounts recognized in the consolidated balance sheets: |  |  |  |
Liability, Defined Benefit Plan, Noncurrent |  | $ 5,237 | $ 6,892 |

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