Other Assets and Liabilities - REO Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2021 USD ($) shares	Sep. 30, 2021 USD ($) asset	Dec. 31, 2020 asset
Other Real Estate [Roll Forward]
Balance at beginning of period	$ 8,413	$ 8,413
Amount related to transfers into REO		21,654
Liquidations		(11,539)
Unrealized gain (loss) resulting from market valuation adjustments on REO		335
Balance at End of Period		18,863
Realized loss from liquidation		$ 300
Number of REO properties recorded on balance sheet \| asset		29	17
5 Arches
Other Assets and Other Liabilities [Line Items]
Shares issued for settlement of remaining deferred consideration \| shares	806,068
Cash payment for contingent consideration liability	$ 1,000
Legacy Sequoia
Other Real Estate [Roll Forward]
Balance at beginning of period	638	$ 638
Amount related to transfers into REO		65
Liquidations		(607)
Unrealized gain (loss) resulting from market valuation adjustments on REO		178
Balance at End of Period		$ 274
Number of REO properties recorded on balance sheet \| asset		2	3
Freddie Mac SLST
Other Real Estate [Roll Forward]
Balance at beginning of period	646	$ 646
Amount related to transfers into REO		2,591
Liquidations		(1,555)
Unrealized gain (loss) resulting from market valuation adjustments on REO		276
Balance at End of Period		$ 1,958
Number of REO properties recorded on balance sheet \| asset		20	9
CAFL
Other Real Estate [Roll Forward]
Balance at beginning of period	2,529	$ 2,529
Amount related to transfers into REO		11,924
Liquidations		(1,990)
Unrealized gain (loss) resulting from market valuation adjustments on REO		(655)
Balance at End of Period		$ 11,808
Number of REO properties recorded on balance sheet \| asset		2	2
Bridge Loan
Other Real Estate [Roll Forward]
Balance at beginning of period	$ 4,600	$ 4,600
Amount related to transfers into REO		7,074
Liquidations		(7,387)
Unrealized gain (loss) resulting from market valuation adjustments on REO		536
Balance at End of Period		$ 4,823
Number of REO properties recorded on balance sheet \| asset		5	3

Business Acquisition, Contingent Consideration, Equity Interest Issued, Number of Shares

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Other Assets and Other Liabilities [Line Items]

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Realized Gain (Loss) From Liquidation

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of cash outflow, not made soon after acquisition date of business combination, to settle contingent consideration liability up to amount recognized at acquisition date, including, but not limited to, measurement period adjustment and less amount paid soon after acquisition date.

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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.

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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.

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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.

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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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