Short-Term Debt - Collateral for Short-Term Debt Facilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Short-term Debt [Line Items]
Total collateral for financing	$ 2,013,399	$ 2,299,034
Facilities
Short-term Debt [Line Items]
Total real estate securities owned	461,938	178,070
Other assets	2,023	1,097
Total collateral for financing	1,726,811	2,017,062
Servicer advance financing
Short-term Debt [Line Items]
Total collateral for financing	286,588	281,972
Cash	17,329	12,713
Restricted cash	0	0
Servicer advances	269,259	269,259
Held-for-sale residential loans \| Facilities
Short-term Debt [Line Items]
Market value of loans pledged as collateral under short-term borrowing agreements	26,282	775,545
Business purpose loans \| Facilities
Short-term Debt [Line Items]
Market value of loans pledged as collateral under short-term borrowing agreements	1,021,051	871,072
HEI \| Facilities
Short-term Debt [Line Items]
Market value of loans pledged as collateral under short-term borrowing agreements	215,517	191,278
On balance sheet \| Facilities
Short-term Debt [Line Items]
Available-for-sale securities pledged as collateral	71,017	72,133
Sequoia \| Sequoia securities \| Short Term Borrowing Agreement \| Facilities
Short-term Debt [Line Items]
Trading securities pledged as collateral	110,821	74,170
Freddie Mac SLST \| Sequoia securities \| Short Term Borrowing Agreement
Short-term Debt [Line Items]
Trading securities pledged as collateral	247,970	0
Freddie Mac K-Series \| Sequoia securities \| Short Term Borrowing Agreement \| Facilities
Short-term Debt [Line Items]
Trading securities pledged as collateral	$ 32,130	$ 31,767

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Restricted Cash Collateral For Borrowed Securities

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- Definition

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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