XML 113 R63.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Fair Value of Financial Instruments - Changes in Level 3 Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2015
Commercial Secured Borrowings |
Liabilities |
Beginning balance | $ 66,707 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue / us-gaap_FairValueByLiabilityClassAxis = rwt_CommercialSecuredLoanMember
Principal paydowns | (152)rwt_FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisLiabilityPaydowns / us-gaap_FairValueByLiabilityClassAxis = rwt_CommercialSecuredLoanMember
Gains (losses) in net income, net | 1,509 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_FairValueByLiabilityClassAxis = rwt_CommercialSecuredLoanMember
Unrealized gains in OCI, net | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome / us-gaap_FairValueByLiabilityClassAxis = rwt_CommercialSecuredLoanMember
Acquisitions | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases / us-gaap_FairValueByLiabilityClassAxis = rwt_CommercialSecuredLoanMember
Sales | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales / us-gaap_FairValueByLiabilityClassAxis = rwt_CommercialSecuredLoanMember
Other settlements, net | 13 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements / us-gaap_FairValueByLiabilityClassAxis = rwt_CommercialSecuredLoanMember
Ending balance | 68,077 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue / us-gaap_FairValueByLiabilityClassAxis = rwt_CommercialSecuredLoanMember
Asset-backed Securities |
Liabilities |
Transfer to FVO | 1,302,216 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3 / us-gaap_FairValueByLiabilityClassAxis = us-gaap_AssetBackedSecuritiesMember
Principal paydowns | (66,517)rwt_FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisLiabilityPaydowns / us-gaap_FairValueByLiabilityClassAxis = us-gaap_AssetBackedSecuritiesMember
Gains (losses) in net income, net | 2,946 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_FairValueByLiabilityClassAxis = us-gaap_AssetBackedSecuritiesMember
Other settlements, net | 421 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements / us-gaap_FairValueByLiabilityClassAxis = us-gaap_AssetBackedSecuritiesMember
Ending balance | 1,239,066 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue / us-gaap_FairValueByLiabilityClassAxis = us-gaap_AssetBackedSecuritiesMember
Residential Loans at Fair Value |
Assets |
Beginning balance | 1,677,984 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = rwt_ResidentialLoansAtFairValueMember
Transfer to FVO | 1,370,699 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_FairValueByAssetClassAxis = rwt_ResidentialLoansAtFairValueMember
Principal paydowns | (111,716)rwt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetCallsMaturitiesPaydowns / us-gaap_FairValueByAssetClassAxis = rwt_ResidentialLoansAtFairValueMember
Gains (losses) in net income, net | (7,570)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_FairValueByAssetClassAxis = rwt_ResidentialLoansAtFairValueMember
Unrealized gains in OCI, net | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_FairValueByAssetClassAxis = rwt_ResidentialLoansAtFairValueMember
Acquisitions | 1,112,042 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_FairValueByAssetClassAxis = rwt_ResidentialLoansAtFairValueMember
Sales | (857,249)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_FairValueByAssetClassAxis = rwt_ResidentialLoansAtFairValueMember
Other settlements, net | (1,916)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_FairValueByAssetClassAxis = rwt_ResidentialLoansAtFairValueMember
Ending balance | 3,197,414 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = rwt_ResidentialLoansAtFairValueMember
Commercial Loans |
Assets |
Beginning balance | 237,496 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialLoanMember
Principal paydowns | (240)rwt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetCallsMaturitiesPaydowns / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialLoanMember
Gains (losses) in net income, net | (7,366)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialLoanMember
Unrealized gains in OCI, net | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialLoanMember
Acquisitions | 92,713 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialLoanMember
Sales | (210,309)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialLoanMember
Ending balance | 127,026 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialLoanMember
Trading Securities |
Assets |
Beginning balance | 111,606 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_TradingAccountAssetsMember
Principal paydowns | (203)rwt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetCallsMaturitiesPaydowns / us-gaap_FairValueByAssetClassAxis = us-gaap_TradingAccountAssetsMember
Gains (losses) in net income, net | 14,114 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_FairValueByAssetClassAxis = us-gaap_TradingAccountAssetsMember
Unrealized gains in OCI, net | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_FairValueByAssetClassAxis = us-gaap_TradingAccountAssetsMember
Acquisitions | 23,084 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_FairValueByAssetClassAxis = us-gaap_TradingAccountAssetsMember
Sales | (13,536)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_FairValueByAssetClassAxis = us-gaap_TradingAccountAssetsMember
Ending balance | 106,837 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_TradingAccountAssetsMember
Available-for-sale Securities |
Assets |
Beginning balance | 1,267,624 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_AvailableforsaleSecuritiesMember
Principal paydowns | (26,110)rwt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetCallsMaturitiesPaydowns / us-gaap_FairValueByAssetClassAxis = us-gaap_AvailableforsaleSecuritiesMember
Gains (losses) in net income, net | (4,306)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_FairValueByAssetClassAxis = us-gaap_AvailableforsaleSecuritiesMember
Unrealized gains in OCI, net | (3,795)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_FairValueByAssetClassAxis = us-gaap_AvailableforsaleSecuritiesMember
Acquisitions | 9,831 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_FairValueByAssetClassAxis = us-gaap_AvailableforsaleSecuritiesMember
Sales | (90,878)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_FairValueByAssetClassAxis = us-gaap_AvailableforsaleSecuritiesMember
Ending balance | 1,178,406 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_AvailableforsaleSecuritiesMember
Liabilities |
Amortization income | 9,838 rwt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAmortizationIncome / us-gaap_FairValueByAssetClassAxis = us-gaap_AvailableforsaleSecuritiesMember
Mortgage Servicing Rights |
Assets |
Beginning balance | 139,293 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = rwt_MortgageServicingRightsMember
Gains (losses) in net income, net | 19,517 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_FairValueByAssetClassAxis = rwt_MortgageServicingRightsMember
Unrealized gains in OCI, net | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_FairValueByAssetClassAxis = rwt_MortgageServicingRightsMember
Acquisitions | 18,754 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_FairValueByAssetClassAxis = rwt_MortgageServicingRightsMember
Sales | (18,206)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_FairValueByAssetClassAxis = rwt_MortgageServicingRightsMember
Ending balance | 120,324 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = rwt_MortgageServicingRightsMember
Guarantee Asset |
Assets |
Beginning balance | 7,201 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = rwt_AssetValueGuaranteesMember
Gains (losses) in net income, net | 1,083 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_FairValueByAssetClassAxis = rwt_AssetValueGuaranteesMember
Ending balance | 6,118 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = rwt_AssetValueGuaranteesMember
Loan Purchase Commitments |
Assets |
Beginning balance | 1,119 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_LoanPurchaseCommitmentsMember
Gains (losses) in net income, net | (20,087)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_FairValueByAssetClassAxis = us-gaap_LoanPurchaseCommitmentsMember
Other settlements, net | (13,781)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_FairValueByAssetClassAxis = us-gaap_LoanPurchaseCommitmentsMember
Ending balance | $ 7,425 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_LoanPurchaseCommitmentsMember

X
- Definition Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Asset, Amortization Income + References No definition available. + Details
Name: | rwt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAmortizationIncome
Namespace Prefix: | rwt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Principal paydowns, including calls and maturities, that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. + References No definition available. + Details
Name: | rwt_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetCallsMaturitiesPaydowns
Namespace Prefix: | rwt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Paydowns + References No definition available. + Details
Name: | rwt_FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisLiabilityPaydowns
Namespace Prefix: | rwt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of sales of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=rwt_AssetValueGuaranteesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=rwt_MortgageServicingRightsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=rwt_ResidentialLoansAtFairValueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_AvailableforsaleSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_CommercialLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_LoanPurchaseCommitmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_TradingAccountAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=rwt_CommercialSecuredLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |