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           Senior Unsecured Notes 
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        6 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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           Jun. 30, 2011 
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| Senior Unsecured Notes | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Senior Unsecured Notes | 
 A summary of the Company's senior unsecured notes as of June 30, 2011 and December 31, 2010 is as follows:  (dollars in thousands) 
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- Definition 
          Senior Unsecured Notes 
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| X | ||||||||||
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- Definition 
          Description of an entity's senior unsecured notes 
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