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Investment Securities - Non-Marketable Securities Included in Other Assets (Details) - USD ($)		9 Months Ended
	Jul. 13, 2023	Sep. 30, 2023	Sep. 30, 2022	Oct. 26, 2023	Dec. 31, 2022
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		$ 2,100,000			$ 2,500,000
Low income housing tax credits and other tax benefits		450,000
Low income housing amortization expense		377,000
Unfunded commitments for low income housing tax credit funds		346,000
Subsequent event
Schedule of Equity Method Investments [Line Items]
Federal home loan bank, dividend rate percentage				8.25%
Visa Inc. Class B common stock
Schedule of Equity Method Investments [Line Items]
Equity securities, FV-NI gain	$ 2,800,000
Low-income housing tax credit investment
Schedule of Equity Method Investments [Line Items]
Impairment losses		0	$ 0
Visa Inc. Class B common stock
Schedule of Equity Method Investments [Line Items]
Number of shares of securities carried at cost (in shares)					10,439
Carrying value of securities carried at cost		0
Asset Derivatives
Schedule of Equity Method Investments [Line Items]
Federal home loan bank stock		$ 16,700,000			$ 16,700,000

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