XML 101 R90.htm IDEA: XBRL DOCUMENT v3.4.0.3

Mortgage Servicing Rights - Details of Retention and Purchase of MSRs (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Mortgage Servicing Rights [Line Items]
MSRs recognized	$ 3,463	$ 15,675
Mortgage servicing rights
Mortgage Servicing Rights [Line Items]
MSRs recognized	8,807	$ 18,754
Associated Principal	870,071
Mortgage servicing rights | Jumbo Loan
Mortgage Servicing Rights [Line Items]
MSRs recognized	46
Associated Principal	6,519
Mortgage servicing rights | Jumbo Loan | Loan Sales
Mortgage Servicing Rights [Line Items]
MSRs recognized	46
Associated Principal	6,519
Mortgage servicing rights | Conforming Loan
Mortgage Servicing Rights [Line Items]
MSRs recognized	8,761
Associated Principal	863,552
Mortgage servicing rights | Conforming Loan | Loan Sales
Mortgage Servicing Rights [Line Items]
MSRs recognized	3,364
Associated Principal	314,518
Mortgage servicing rights | Conforming Loan | From purchases
Mortgage Servicing Rights [Line Items]
MSRs recognized	5,397
Associated Principal	$ 549,034

X

- Definition

Mortgage Servicing Rights [Line Items]

+ References

No definition available.

+ 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=56950315&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=56950315&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:

X

- Details

Name:	us-gaap_MortgageLoansOnRealEstateLoanTypeAxis=rwt_JumboLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=rwt_LoanSalesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MortgageLoansOnRealEstateLoanTypeAxis=rwt_ConformingLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=rwt_LoanPurchasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: