Short-Term Debt - Collateral for Short-Term Debt Facilities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Short-term Debt [Line Items]
Total collateral for financing	$ 2,225,880	$ 2,450,304
Facilities
Short-term Debt [Line Items]
Total real estate securities owned	124,382	99,005
Other assets	2,512	1,962
Total collateral for financing	1,912,053	2,107,451
Servicer advance financing
Short-term Debt [Line Items]
Total collateral for financing	313,827	342,853
Cash	14,381	6,480
Restricted cash	26,236	25,420
Servicer advances	273,210	310,953
Held-for-sale residential loans \| Facilities
Short-term Debt [Line Items]
Market value of loans pledged as collateral under short-term borrowing agreements	1,207,185	1,838,797
Business purpose loans \| Facilities
Short-term Debt [Line Items]
Market value of loans pledged as collateral under short-term borrowing agreements	577,974	167,687
On balance sheet \| Facilities
Short-term Debt [Line Items]
Available-for-sale securities pledged as collateral	10,014	5,823
Sequoia \| Sequoia securities \| Short Term Borrowing Agreement \| Facilities
Short-term Debt [Line Items]
Trading securities pledged as collateral	82,636	61,525
Freddie Mac K-Series \| Sequoia securities \| Short Term Borrowing Agreement \| Facilities
Short-term Debt [Line Items]
Trading securities pledged as collateral	$ 31,732	$ 31,657

Restricted Cash and Other Assets Pledged as Collateral

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Restricted Cash Collateral For Borrowed Securities

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Servicer Advances Collateral

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- Definition

Short Term Debt, Restricted

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Short-term Debt Pledged as Collateral

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Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value of the securities pledged as collateral against securities loaned.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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