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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
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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Federal Home Loan Bank, Dividend Rate, Percentage

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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
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Section S50
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