Mortgage Loans (Details) - Table - Redemption Terms - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Loans and Leases Receivable Disclosure [Line Items] | ||
| Allowance for credit losses on mortgage loans | $ 1 | $ 1 |
| Mortgage loans held for portfolio, net of allowance for credit losses | 601 | 639 |
| Accrued Interest Receivable | 80 | 67 |
| Fixed rate medium-term mortgage loans | ||
| Loans and Leases Receivable Disclosure [Line Items] | ||
| Unpaid principal balance | 8 | 9 |
| Fixed Rate Long Term mortgage loans | ||
| Loans and Leases Receivable Disclosure [Line Items] | ||
| Unpaid principal balance | 564 | 599 |
| Residential Portfolio Segment | ||
| Loans and Leases Receivable Disclosure [Line Items] | ||
| Unpaid principal balance | 572 | 608 |
| Unamortized premiums | 31 | 33 |
| Unamortized discounts | (1) | (1) |
| Mortgage Loans Held For Portfolio | 602 | 640 |
| Allowance for credit losses on mortgage loans | 1 | 1 |
| Mortgage loans held for portfolio, net of allowance for credit losses | 601 | 639 |
| Accrued Interest Receivable | $ 4 | $ 5 |
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- Definition Reflects the cumulative amount of discounts from the face amount of loans that are being amortized into income as an adjustment of yield. No definition available.
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- Definition Reflects the cumulative amount of premiums over the face amount of loans that are being amortized into income as an adjustment of yield. No definition available.
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- Definition Amount, after allowance for credit loss, of accrued interest on financing receivable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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 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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- 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. No definition available.
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