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Real Estate Securities - Summary of Significant Valuation Assumptions for Available for Sale Securities (Detail) - Jun. 30, 2015 | Total
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Prime | Minimum |
Schedule of Available-for-sale Securities [Line Items] |
Prepayment rates | 8.00%
Projected default rate | 1.00%
Prime | Maximum |
Schedule of Available-for-sale Securities [Line Items] |
Prepayment rates | 16.00%
Projected default rate | 21.00%
Non-prime | Minimum |
Schedule of Available-for-sale Securities [Line Items] |
Prepayment rates | 8.00%
Projected default rate | 14.00%
Non-prime | Maximum |
Schedule of Available-for-sale Securities [Line Items] |
Prepayment rates | 12.00%
Projected default rate | 18.00%

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- Definition This item represents a significant valuation assumption on prepayment rates, represented as a percentage, which was considered as one of the potential factors in reaching a conclusion that the available-for-sale investments are not other-than-temporarily impaired. + References No definition available. + Details
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- Definition This item represents the default rate of the underlying assets in the security that were considered as one of the potential factors in reaching a conclusion that the available-for-sale investments are not other-than-temporarily impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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