| **Pension and Other Post Retirement Benefit Plans Pension and Other Post Retirement Benefit Plans - Health Insurance Plan (Details) (USD $)In Thousands, unless otherwise specified** | 12 Months Ended |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Schedule Of Postemployment Plan [Line Items]**                                                                                                                                      |            |   |   |
| Percentange of the Premiums Paid By Plan Participants                                                                                                                                 | 100.00%         |   |   |
| Accrued Benefits Payable                                                                                                                                                              | $ 4,035         | $ 4,116 |   |
| Post retirement plan expense                                                                                                                                                          | $ 477           | $ 528 | $ 574 |
| Minimum                                                                                                                                                                               |            |   |   |
| **Schedule Of Postemployment Plan [Line Items]**                                                                                                                                      |            |   |   |
| Age of Plan Participants                                                                                                                                                              | 55 years        |   |   |
| Maximum                                                                                                                                                                               |            |   |   |
| **Schedule Of Postemployment Plan [Line Items]**                                                                                                                                      |            |   |   |
| Age of Plan Participants                                                                                                                                                              | 65 years        |   |   |

| X                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Defined Benefit Plan, Other Postretirement Benefit, Participant Attained Age
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Defined Benefit Plan, Other Postretirement Benefit, Percent of Premiums Paid by Participant
+ References
No definition available.
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| X                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of costs recognized during the period for non-pension postretirement benefits, such as medical, dental and life insurance.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This represents the entire liability recognized in the balance sheet that is associated with other postretirement defined benefit plans (excluding pension plans).
+ References
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