Mortgage Loans Held-for-Portfolio - Schedule of Information on Mortgage Loans Held-for-portfolio (Details) - USD ($) $ in Thousands |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||
| Total unpaid principal balance | $ 2,866,013 | $ 2,599,157 |
| Unamortized premiums | 60,028 | 50,092 |
| Unamortized discounts | (637) | (611) |
| Basis adjustment | (2,445) | (498) |
| Total mortgage loans amortized cost | 2,922,959 | 2,648,140 |
| Allowance for credit losses | (4,948) | (3,691) |
| Total mortgage loans held-for-portfolio at carrying value | $ 2,918,011 | $ 2,644,449 |
| Percentage of Total | 100.00% | 100.00% |
| Fixed medium-term single-family mortgages | ||
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||
| Total unpaid principal balance | $ 88,004 | $ 97,276 |
| Percentage of Total | 3.07% | 3.74% |
| Fixed long-term single-family mortgages | ||
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||
| Total unpaid principal balance | $ 2,778,009 | $ 2,501,881 |
| Percentage of Total | 96.93% | 96.26% |
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- Definition Financing Receivable, Basis Adjustments No definition available.
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- Definition Financing Receivable, Excluding Accrued Interest, Before Allowance For Credit Loss, Fee, And Loan In Process, Percentage No definition available.
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- Definition Financing Receivable, Unamortized Purchase Discount No definition available.
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- Definition Financing Receivable, Unamortized Purchase Premium No definition available.
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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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