Short-Term Debt - Schedule of Collateral for Short-Term Debt Facilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Short-term Debt [Line Items]
Total Collateral for Short-Term Debt Facilities	$ 1,855,214	$ 2,299,034
Non-Recourse BPL Financing
Short-term Debt [Line Items]
Total real estate securities owned	122,111	178,070
Restricted cash and other assets	0	1,097
Total Collateral for Short-Term Debt Facilities	1,439,611	2,017,062
Servicer advance financing
Short-term Debt [Line Items]
Cash collateral for borrowed securities	15,162	12,713
Servicer advances	225,345	269,259
Subordinate securities financing
Short-term Debt [Line Items]
Cash collateral for borrowed securities	175,096	0
Residential loans, held-for-sale, at fair value \| Non-Recourse BPL Financing
Short-term Debt [Line Items]
Short term debt, restricted	907,742	775,545
Residential MSR warehouse \| Non-Recourse BPL Financing
Short-term Debt [Line Items]
Short term debt, restricted	76,560	0
Business purpose loans \| Non-Recourse BPL Financing
Short-term Debt [Line Items]
Short term debt, restricted	95,225	871,072
HEI \| Non-Recourse BPL Financing
Short-term Debt [Line Items]
Short term debt, restricted	237,973	191,278
On balance sheet \| Non-Recourse BPL Financing
Short-term Debt [Line Items]
On balance sheet	4,460	72,133
Sequoia \| Sequoia securities \| Short Term Borrowing Agreement \| Non-Recourse BPL Financing
Short-term Debt [Line Items]
Trading securities pledged as collateral	52,333	74,170
Freddie Mac K-Series \| Sequoia securities \| Short Term Borrowing Agreement \| Non-Recourse BPL Financing
Short-term Debt [Line Items]
Trading securities pledged as collateral	33,308	31,767
Net investments in consolidated CAFL Term entities \| Sequoia securities \| Short Term Borrowing Agreement
Short-term Debt [Line Items]
Trading securities pledged as collateral	$ 32,010	$ 0

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Servicer Advances Collateral

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
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-Name Accounting Standards Codification
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
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Fair value of the securities pledged as collateral against securities loaned.

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-Topic 210
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-Section 55
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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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