XML 160 R106.htm IDEA: XBRL DOCUMENT v2.4.1.9

Details of Retention and Purchase of MSRs (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Mortgage Servicing Rights [Line Items]
MSR Fair Value	$ 48,000us-gaap_ServicingAssetAtFairValueAdditions	$ 44,063us-gaap_ServicingAssetAtFairValueAdditions	$ 7,329us-gaap_ServicingAssetAtFairValueAdditions
Mortgage Servicing Rights
Mortgage Servicing Rights [Line Items]
MSR Fair Value	95,550us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	47,514us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Associated Principal	8,672,671us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	5,223,399us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Mortgage Servicing Rights | Jumbo MSR Additions
Mortgage Servicing Rights [Line Items]
MSR Fair Value	9,006us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	44,012us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Associated Principal	1,061,028us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	4,911,623us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Mortgage Servicing Rights | Jumbo MSR Additions | Securitization
Mortgage Servicing Rights [Line Items]
MSR Fair Value	8,518us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_SecuritizationsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	42,920us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_SecuritizationsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Associated Principal	1,002,235us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_SecuritizationsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	4,787,264us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_SecuritizationsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Mortgage Servicing Rights | Jumbo MSR Additions | Loan Sales
Mortgage Servicing Rights [Line Items]
MSR Fair Value	488us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanSalesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	1,092us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanSalesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Associated Principal	58,793us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanSalesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	124,359us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_JumboMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanSalesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Mortgage Servicing Rights | Conforming MSR Additions
Mortgage Servicing Rights [Line Items]
MSR Fair Value	86,544us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	3,502us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Associated Principal	7,611,643us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	311,776us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Mortgage Servicing Rights | Conforming MSR Additions | Loan Sales
Mortgage Servicing Rights [Line Items]
MSR Fair Value	38,995us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanSalesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	52us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanSalesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Associated Principal	3,618,256us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanSalesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	5,107us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanSalesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Mortgage Servicing Rights | Conforming MSR Additions | From purchases
Mortgage Servicing Rights [Line Items]
MSR Fair Value	47,549us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanPurchasesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	3,450us-gaap_ServicingAssetAtFairValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanPurchasesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember
Associated Principal	$ 3,993,387us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanPurchasesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember	$ 306,669us-gaap_ServicingAssetAtAmortizedValueAdditions / us-gaap_FairValueByFairValueHierarchyLevelAxis = rwt_ConformingMortgageServicingRightsAdditionsMember / us-gaap_FinancialInstrumentAxis = rwt_LoanPurchasesMember / us-gaap_InvestmentTypeAxis = rwt_MortgageServicingRightsMember

X

- Details

Name:	rwt_MortgageServicingRightsLineItems
Namespace Prefix:	rwt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 4

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122739-111746

+ Details

Name:	us-gaap_ServicingAssetAtAmortizedValueAdditions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

The 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.

+ References

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

+ Details

Name:	us-gaap_ServicingAssetAtFairValueAdditions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

Name:	us-gaap_InvestmentTypeAxis=rwt_MortgageServicingRightsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: