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Other Assets and Other Liabilities [Line Items]

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

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Aggregate amount of net income allocated to limited partners.

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The number of real estate properties owned as of the balance sheet 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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Other Assets and Liabilities - Additional Information (Details) $ in Thousands	3 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2019 USD ($) property	Dec. 31, 2018 USD ($) partnership property	Sep. 30, 2019 USD ($) property	Dec. 31, 2018 USD ($) partnership property
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 5,069	$ 3,943	$ 5,069	$ 3,943
REO liquidations			5,000
Unrealized gain resulting from market valuation adjustments on REO			1,000
Number of partnerships consolidated \| partnership		2		2
Payable to minority partner	18,664	$ 14,331	18,664	$ 14,331
Net gain allocated to Limited Partners	400		900
Legacy Sequoia
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 500		500
Amount related to transfers into REO			$ 200
Number of REO properties recorded on balance sheet \| property	3	13	3	13
Freddie Mac SLST
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 100		$ 100
Amount related to transfers into REO			100
Bridge Loan \| Debt Securities
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 5,000		5,000
Amount related to transfers into REO			$ 5,000
Number of REO properties recorded on balance sheet \| property	1		1