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Investment Securities - Non-Marketable Securities Included in Other Assets (Details) - USD ($)	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Oct. 24, 2024	Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]
Federal home loan bank stock, par value (in usd per share)	$ 100
Investments in low income housing tax credit funds	$ 1,700,000			$ 2,000,000.0
Low income housing tax credits and other tax benefits	394,000
Low income housing amortization expense	328,000
Unfunded commitments for low income housing tax credit funds	342,000
Impairment losses	0	$ 0
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	$ 16,700,000			$ 16,700,000

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Amount of investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under program not meeting condition for accounting under proportional amortization method.

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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).

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