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Postretirement Medical Plan
3 Months Ended
Mar. 31, 2013
Postretirement Medical Plan  
Postretirement Medical Plan

10.  Postretirement Medical Plan

 

We maintain an unfunded postretirement medical plan to provide certain postretirement medical benefits to eligible employees.  Net periodic postretirement benefit costs included the following components (in thousands):

 

 

 

Three Months Ended

 

 

 

March 31,

 

 

 

2013

 

2012

 

Service Cost

 

$

1,238

 

$

1,053

 

Interest Cost

 

418

 

356

 

Amortization of prior service cost

 

444

 

394

 

Net periodic benefit cost

 

$

2,100

 

$

1,803