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Investment Securities - Non-Marketable Securities Included in Other Assets Narrative (Details) - USD ($)		12 Months Ended
	Jul. 13, 2023	Dec. 31, 2023	Dec. 31, 2022	Feb. 21, 2024
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		$ 2,000,000	$ 2,500,000
Low income housing tax credits and other tax benefits		600,000
Low income housing amortization expense		503,000
Unfunded commitments for low income housing tax credit funds		344,000
Impairment losses		$ 0	$ 0
Subsequent event
Schedule of Equity Method Investments [Line Items]
Federal home loan bank, dividend rate percentage				8.75%
Visa Inc. Class B common stock
Schedule of Equity Method Investments [Line Items]
Equity securities, FV-NI gain	$ 2,800,000
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	10,439
Carrying value of securities carried at cost		$ 0	$ 0
Other assets
Schedule of Equity Method Investments [Line Items]
Federal home loan bank stock		$ 16,700,000	$ 16,700,000

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