Number Of Partnerships Consolidated

No definition available.

Name:	rwt_NumberOfPartnershipsConsolidated
Namespace Prefix:	rwt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Other Assets and Other Liabilities [Line Items]

+ References

No definition available.

+ Details

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

- Definition

Carrying amount of the equity interests owned by noncontrolling partners of a limited partnership included in the entity's consolidated financial statements.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestInLimitedPartnerships
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Aggregate amount of net income allocated to limited partners.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

+ Details

Name:	us-gaap_NetIncomeLossAllocatedToLimitedPartners
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of realized and unrealized gain (loss), from the firm's direct investment activity, conducted separately from customer trading activities, and includes, but is not limited to, investments in private equity, alternative investment products, real estate, and exchanges and memberships.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2,3)
-URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(g),(h))
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

+ Details

Name:	us-gaap_PrincipalInvestmentGainsLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5162-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4437-111522

+ Details

Name:	us-gaap_RealEstateAcquiredThroughForeclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of real estate investments acquired through foreclosure for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28(Footnote 4))
-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

+ Details

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

- Definition

Amount of real estate investments sold for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

+ Details

Name:	us-gaap_RealEstateCostOfRealEstateSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=rwt_LegacySequoiaSecuritizationEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=rwt_FreddieMacSLSTMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=rwt_CAFLSecuritizationEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_BridgeLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Other Assets and Liabilities - Additional Information (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2019 USD ($) property	Dec. 31, 2018 USD ($) partnership property	Dec. 31, 2019 USD ($) property	Dec. 31, 2018 USD ($) partnership property
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 9,462	$ 3,943	$ 9,462	$ 3,943
REO liquidations			5,000
Unrealized gain on REO from market value adjustments			1,000
Number of partnerships consolidated \| partnership		2		2
Payable to minority partner	13,189	$ 14,331	13,189	$ 14,331
Co-investors gains (losses)			1,000	$ (100)
Legacy Sequoia
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 500		$ 500
Number of REO properties recorded on balance sheet \| property	4	13	4	13
Amount related to transfers into REO			$ 300
Freddie Mac SLST
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 400		$ 400
Number of REO properties recorded on balance sheet \| property	3		3
Amount related to transfers into REO			$ 500
CAFL
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 2,000		$ 2,000
Number of REO properties recorded on balance sheet \| property	2		2
Amount related to transfers into REO	$ 3,000
Debt Securities \| Bridge Loan
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 7,000		$ 7,000
Number of REO properties recorded on balance sheet \| property	4		4
Amount related to transfers into REO			$ 8,000