Short-Term Debt - Collateral for Short-Term Debt Facilities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Short-term Debt [Line Items]
Total Collateral for Short-Term Debt Facilities	$ 1,531,035	$ 1,855,214
CAFL \| Sequoia securities \| Short Term Borrowing Agreement
Short-term Debt [Line Items]
Trading securities pledged as collateral	32,336	32,010
Facilities
Short-term Debt [Line Items]
Total real estate securities owned	114,010	122,111
Restricted cash and other assets	580	0
Total Collateral for Short-Term Debt Facilities	987,497	1,439,611
Facilities \| On balance sheet
Short-term Debt [Line Items]
On balance sheet	4,470	4,460
Facilities \| Sequoia \| Sequoia securities \| Short Term Borrowing Agreement
Short-term Debt [Line Items]
Trading securities pledged as collateral	43,653	52,333
Facilities \| Freddie Mac K-Series \| Sequoia securities \| Short Term Borrowing Agreement
Short-term Debt [Line Items]
Trading securities pledged as collateral	33,551	33,308
Recourse subordinate securities financing
Short-term Debt [Line Items]
Cash	313,148	175,096
Servicer advance financing
Short-term Debt [Line Items]
Cash	14,357	15,162
Servicer advances	216,033	225,345
Held-for-sale residential consumer loans \| Facilities
Short-term Debt [Line Items]
Short term debt, restricted	507,450	907,742
MSRs \| Facilities
Short-term Debt [Line Items]
Short term debt, restricted	84,831	76,560
Residential investor loans \| Facilities
Short-term Debt [Line Items]
Short term debt, restricted	40,961	95,225
HEI \| Facilities
Short-term Debt [Line Items]
Short term debt, restricted	$ 239,665	$ 237,973

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Servicer Advances Collateral

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- Definition

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- Definition

Short-term Debt Pledged as Collateral

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- Definition

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
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
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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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