Securities - Additional Information (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Sale proceeds	$ 130,912,000	$ 0	$ 0
Gross gains	1,300,000	0
Gross losses	248,000	0
Securities, carrying value	578,000,000.0	581,100,000
Equity securities, at fair value	14,694,000	16,473,000
Proceeds from sales of equity securities	4,148,000	1,287,000	2,155,000
(Loss) gain on equity securities	$ (552,000)	$ 496,000	$ (583,000)
Redemption of funds	60 days
Unfunded commitments	$ 0
Fair value of securities	11,200,000
Community Reinvestment Funds
Debt Securities, Available-for-sale [Line Items]
Equity securities, at fair value	3,500,000
Other Financial Institutions
Debt Securities, Available-for-sale [Line Items]
Unfunded commitments	$ 0

Investment in community development loans mortgage backed securities small business loans.

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Proceeds from Sale of Equity Securities, FV-NI

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Securities pledged to secure public deposit carrying value.

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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