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USDfalsefalse$eol_PE798-----1310-Q0007_STD_182_20120630_0_710256x762297http://www.sec.gov/CIK0000930236duration2012-01-01T00:00:002012-06-30T00:00:00iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 3rwt_MortgageServicingRightsLineItemsrwt_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Mortgage Servicing Rights [Line Items]2false 4rwt_PrincipalAmountOfLoansSecuritizedDuringPeriodrwt_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse18000000001800000000USD$falsetruefalse2falsefalsefalse00falsefalsefalse3truefalsefalse40400000004040000000USD$falsetruefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryPrincipal Amount Of Loans Securitized During PeriodNo definition available.false2Residential loans transferred to securitization entities3false 4us-gaap_ServicingAssetAtFairValueAdditionsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse1600000016000000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse2900000029000000USD$falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 3 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122625-111746 false2MSRs at a taxable REIT subsidiary4false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse3false USDtruefalse$eol_PE798-----1310-Q0007_STD_91_20130630_0_710256x762297http://www.sec.gov/CIK0000930236duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseMortgage Servicing Rightsus-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldirwt_MortgageServicingRightsMemberus-gaap_InvestmentTypeAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Mortgage Servicing Rights5true 3rwt_MortgageServicingRightsLineItemsrwt_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Mortgage Servicing Rights [Line Items]6false 4us-gaap_ServicingAssetAtFairValueAdditionsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse1614800016148000USD$falsefalsefalse2truefalsefalse10290001029000USD$falsefalsefalse3truefalsefalse2861400028614000USD$falsefalsefalse4truefalsefalse26080002608000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 3 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122625-111746 false2MSRs at a taxable REIT subsidiary7false 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