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Fair Value Measurements (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Fair value measurements |  |  |
Fair value carrying amount |  | $ 7,110 | $ 2,569
Mortgages held for sale reported at fair value |  |  |
Fair value measurements |  |  |
Fair value carrying amount |  | 7,110 | 2,569
Aggregate unpaid principal |  | 6,816 | 2,343
Excess of fair value carrying amount over (under) unpaid principal | [1] | $ 294 | $ 226
[1] | The excess of fair value carrying amount over (under) unpaid principal is included in mortgage banking income and includes changes in fair value at and subsequent to funding and gains and losses on the related loan commitment prior to funding.

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- Definition This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (d)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 + Details
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- Definition This is the principal amount outstanding for loans which are in the process of being securitized as of the date of the statement of financial position (across all types of loans). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Subparagraph (a) -Paragraph 4 -SubTopic 20 -Topic 860 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481326/860-20-50-4 + Details
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