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Investment Securities - Non-Marketable Securities Included in Other Assets (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Apr. 25, 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	$ 1,900,000			$ 2,000,000
Low income housing tax credits and other tax benefits	133,000
Low income housing amortization expense	111,000
Unfunded commitments for low income housing tax credit funds	343,000
Impairment losses	0	$ 0
Subsequent event
Schedule of Equity Method Investments [Line Items]
Federal home loan bank, dividend rate percentage			8.25%
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 in qualified affordable housing projects.

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