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Investment Securities - Non-Marketable Securities Included in Other Assets (Details) - USD ($) $ / shares in Units, $ in Millions | Oct. 23, 2025 | Sep. 30, 2025 | Dec. 31, 2024
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Schedule of Equity Method Investments [Line Items] |  |  |
Federal home loan bank stock, par value (in usd per share) |  | $ 100 |
Subsequent Event |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Federal home loan bank, dividend rate percentage | 8.75% |  |
Asset derivatives |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Federal home loan bank stock |  | $ 16.7 | $ 16.7

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- Definition Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 325 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477974/942-325-45-1 + Details
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