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Deposits securing credit risk transfers pledged to creditors.

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No definition available.

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Derivative assets pledged to creditors.

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- Definition

Long term debt average balance during period.

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No definition available.

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- Definition

Mortgage servicing rights, secured notes payable.

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No definition available.

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Notes payable gross.

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No definition available.

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- Definition

Servicing advances secured notes payable

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No definition available.

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- Definition

Aggregate amount of interest paid or due on all long-term debt.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1402
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-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
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-Publisher FASB
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Weighted average interest rate of long-term debt outstanding calculated over time.

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
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- Definition

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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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

No definition available.

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Long-Term Debt - Summary of Financial Information Relating to Note Payable Secured by Credit Risk Transfer and Mortgage Servicing Assets (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Carrying value:
Balance	$ 2,503,473		$ 2,503,473		$ 2,258,128
Freddie Mac Mortgage Servicing Rights Financing [Member]
Carrying value:
Carrying value of notes	2,508,297		2,508,297		2,261,846
Assets securing notes payable:
Mortgage servicing rights at fair value	3,430,494		3,430,494		3,582,211
Servicing advances	20,644		20,644		33,777
Deposits securing CRT arrangements			776,961		832,640
Notes Payable [Member] \| Freddie Mac Mortgage Servicing Rights Financing [Member]
Carrying value:
Unamortized debt issuance costs	$ (4,824)		$ (4,824)		$ (3,718)
Weighted average interest rate	6.78%		6.78%		6.91%
Assets securing notes payable:
Derivative assets	$ 21,153		$ 21,153		$ 20,037
Notes Payable [Member] \| Freddie Mac MSR Financing
Short Term Debt [Line Items]
Average balance	$ 2,514,586	$ 2,539,717	$ 2,444,848	$ 2,693,728
Weighted-average interest rate	6.78%	7.69%	6.89%	7.64%
Total interest expense	$ 44,943	$ 51,465	$ 131,614	$ 160,524
Credit Risk Transfer Arrangement Financing [Member] \| Freddie Mac Mortgage Servicing Rights Financing [Member]
Carrying value:
Carrying value of notes	568,630		568,630		608,903
Freddie Mac Credit Agreements [Member] \| Fannie Mae Mortgage Servicing Rights Financing [Member]
Carrying value:
Carrying value of notes	725,000		725,000		725,000
Freddie Mac Credit Agreements [Member] \| Freddie Mac Mortgage Servicing Rights And Servicing Advance Receivables Financing [Member]
Carrying value:
Carrying value of notes	$ 1,214,667		$ 1,214,667		$ 927,943