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           SEGMENT REPORTING AND VARIABLE INTEREST ENTITIES - Holdings in Variable Interest Entities (Details 2) (USD $) 
        In Thousands, unless otherwise specified  | 
        
           Dec. 31, 2013 
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|---|---|---|---|---|---|---|---|---|---|---|
| Carrying Value of Newcastle's Investment | $ 2,002 | |||||||||
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           VIE | CDO V 
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| Gross Assets | 200,616 | [1] | ||||||||
| Debt | 226,615 | [2] | ||||||||
| Carrying Value of Newcastle's Investment | 2,002 | [3] | ||||||||
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           VIE | CDO VIII Repack 
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| Gross Assets | 146,645 | [1],[4] | ||||||||
| Debt | 146,645 | [2],[4] | ||||||||
| Carrying Value of Newcastle's Investment | $ 104,308 | [3],[4] | ||||||||
          
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- Definition 
          The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition 
          The net carrying amount of the consolidated Variable Interest Entity's assets and liabilities included in the reporting entity's statement of financial position. No definition available. 
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| X | ||||||||||
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- Definition 
          The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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