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Retirement And Other Postretirement Benefit Plans (Tables) | 3 Months Ended
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Mar. 31, 2012
Retirement And Other Postretirement Benefit Plans [Abstract] |
Net Periodic Benefit Cost For The Defined Benefit Plans |
|  | Three Months Ended |
|  | March 31, |
|  | 2012 |  |  | 2011 |
Service cost |  | $ | 17 |  |  | $ | 7 |
Interest cost |  |  | 1,541 |  |  |  | 1,699 |
Expected return on plan assets |  |  | (1,934 | ) |  |  | (1,891 | )
Amortization: |  |  |  |  |  |  |  |
Unrecognized net transition asset |  |  | (23 | ) |  |  | (23 | )
Unrecognized prior service cost (credit) |  |  | 2 |  |  |  | 2 |
Unrecognized loss |  |  | 447 |  |  |  | 294 |
Net periodic pension benefit cost |  | $ | 50 |  |  | $ | 88 |
Net Periodic Postretirement Benefit Cost |
|  | Three Months Ended |
|  | March 31, |
|  | 2012 |  |  | 2011 |
Interest cost |  | $ | 12 |  |  | $ | 14 |
Amortization of unrecognized loss |  |  | 3 |  |  |  | 1 |
Net periodic postretirement benefit cost |  | $ | 15 |  |  | $ | 15 |

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