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Pension and Other Postretirement Benefits (Tables) | 9 Months Ended
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Sep. 30, 2012
Schedule of Components of Net Periodic Benefit Cost | Pension and Other Postretirement Benefits – The components of net periodic benefit cost were as follows:
|  | Third quarter ended September 30, |  |  | Nine months ended September 30, |
Pension benefits |  | 2012 |  |  | 2011 |  |  | 2012 |  |  | 2011 |
Service cost |  | $ | 46 |  |  | $ | 41 |  |  | $ | 139 |  |  | $ | 123 |
Interest cost |  |  | 160 |  |  |  | 169 |  |  |  | 480 |  |  |  | 509 |
Expected return on plan assets |  |  | (202 | ) |  |  | (202 | ) |  |  | (605 | ) |  |  | (605 | )
Amortization of prior service cost |  |  | 5 |  |  |  | 5 |  |  |  | 14 |  |  |  | 14 |
Recognized net actuarial loss |  |  | 97 |  |  |  | 63 |  |  |  | 288 |  |  |  | 187 |
Net periodic benefit cost |  | $ | 106 |  |  | $ | 76 |  |  | $ | 316 |  |  | $ | 228 |
|  | Third quarter ended September 30, |  |  | Nine months ended September 30, |
Other postretirement benefits |  | 2012 |  |  | 2011 |  |  | 2012 |  |  | 2011 |
Service cost |  | $ | 3 |  |  | $ | 5 |  |  | $ | 10 |  |  | $ | 13 |
Interest cost |  |  | 33 |  |  |  | 40 |  |  |  | 99 |  |  |  | 119 |
Expected return on plan assets |  |  | — |  |  |  | (1 | ) |  |  | — |  |  |  | (2 | )
Amortization of prior service benefit |  |  | (4 | ) |  |  | (5 | ) |  |  | (12 | ) |  |  | (13 | )
Recognized net actuarial loss |  |  | 7 |  |  |  | 7 |  |  |  | 19 |  |  |  | 20 |
Net periodic benefit cost |  | $ | 39 |  |  | $ | 46 |  |  | $ | 116 |  |  | $ | 137 |

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