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           Mortgage Loans Held-for-Investment in Securitization Trust, at Fair Value Mortgage Loans Held-for-Investment in Securitization Trust, at Fair Value (Notes) 
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           Jun. 30, 2013 
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| Mortgage Loans Held-for-Investment, at Fair Value [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||
| Loans, Notes, Trade and Other Receivables Disclosure [Text Block] | 
 Mortgage Loans Held-for-Investment in Securitization Trust, at Fair Value 
During the six months ended June 30, 2013, the Company purchased subordinated debt and excess servicing rights from a securitization trust issued by a third party. The underlying residential mortgage loans held by the trust, which are consolidated on the Company's condensed consolidated balance sheet, are classified as mortgage loans held-for-investment in securitization trust and carried at fair value as a result of a fair value option election. See Note 3 - Variable Interest Entities for additional information regarding consolidation of the securitization trust. The following table presents the carrying value of the Company's mortgage loans held-for-investment in securitization trust as of June 30, 2013 and December 31, 2012:
 
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- Definition 
          The entire disclosure of mortgage loans to individuals not classified as held for sale but are held-for-investment. No definition available. 
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