Other Assets and Liabilities - Additional Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) property	Sep. 30, 2020 USD ($) property	Dec. 31, 2019 USD ($) property
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 8,535	$ 8,535	$ 9,462
REO liquidations	13,000
Unrealized gain (loss) resulting from market valuation adjustments on REO		(300)
Legacy Sequoia
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 1,000	$ 1,000
Number of REO properties recorded on balance sheet \| property	3	3	4
Amount related to transfers into REO	$ 1,000
Freddie Mac SLST
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 1,000	$ 1,000
Number of REO properties recorded on balance sheet \| property	9	9	3
Amount related to transfers into REO	$ 1,000
CAFL
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 4,000	$ 4,000
Number of REO properties recorded on balance sheet \| property	3	3	2
Amount related to transfers into REO	$ 6,000
Bridge Loan \| Debt Securities
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 3,000	$ 3,000
Number of REO properties recorded on balance sheet \| property	2	2	4
Amount related to transfers into REO	$ 5,000

Other Assets and Other Liabilities [Line Items]

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

+ References

No definition available.

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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)
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- 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=121611835&loc=d3e5162-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
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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))
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Amount of real estate investments sold for entities with a substantial portion of business acquiring and holding investment real estate.

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