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Excludes loans and leases covered under loss sharing agreements.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5074-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5066-111524 false2Carrying value22false 4us-gaap_MortgageLoansOnRealEstatePeriodIncreaseDecreaseus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse3800038000USD$falsefalsefalse2truefalsefalse405000405000USD$falsefalsefalse3truefalsefalse7800078000USD$falsefalsefalse4truefalsefalse498000498000USD$falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe total periodic movement (increases and decreases) in the carrying amount of mortgage loans on real estate.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule IV) -URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 29 -Article 12 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule IV -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-29.6) -URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014 false2Valuation adjustments23false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse15false USDtruefalse$eol_PE798-----1310-Q0007_STD_91_20130630_0_713971x785036http://www.sec.gov/CIK0000930236duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseResidential Loans Held for Investmentus-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxisxbrldihttp://xbrl.org/2006/xbrldirwt_ResidentialLoansHeldForInvestmentMemberus-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxisexplicitMemberiso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170pureStandardhttp://www.xbrl.org/2003/instancepure0CreditScoreStandardhttp://www.redwoodtrust.com/20130630CreditScorerwt0USDUSD$nanafalse0Residential Loans Held for Investment24true 3us-gaap_MortgageLoansOnRealEstateLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Mortgage Loans on Real Estate [Line Items]25false 4us-gaap_PrincipalAmountOutstandingOnLoansManagedAndSecuritizedus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse20015440002001544000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse20015440002001544000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse22780690002278069000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719 false2Principal value26false 4us-gaap_LoansAndLeasesReceivableNetReportedAmountConsumerus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse19981780001998178000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse19981780001998178000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse22728120002272812000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of consumer loans, including, but not limited to, mortgage, home equity, vehicles, credit card, installment, and lease financing. 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