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Real Estate Securities - Summary of Significant Valuation Assumptions for Available for Sale Securities (Detail) | 3 Months Ended
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Mar. 31, 2016
Prime | Minimum |
Schedule of Available-for-sale Securities [Line Items] |
Prepayment rates | 10.00%
Projected default rate | 0.00%
Prime | Maximum |
Schedule of Available-for-sale Securities [Line Items] |
Prepayment rates | 20.00%
Projected default rate | 9.00%
Non-prime |
Schedule of Available-for-sale Securities [Line Items] |
Projected default rate | 5.00%
Non-prime | Minimum |
Schedule of Available-for-sale Securities [Line Items] |
Prepayment rates | 12.00%
Non-prime | Maximum |
Schedule of Available-for-sale Securities [Line Items] |
Prepayment rates | 15.00%

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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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Namespace Prefix: | rwt_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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