Securities - Additional Information (Details)	12 Months Ended
Dec. 31, 2020 USD ($) security	Dec. 31, 2019 USD ($) security	Dec. 31, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items]
Tax provision related to net realized gains	$ 460,000	$ 31,000	$ 0
Federal home loan balance	$ 1,182,510,000
Number of securities holdings \| security	0	0
Shareholders equity, percentage	10.00%	10.00%
Proceeds from sale of securities, operating activities	$ 5,935,000	$ 301,000	455,000
Net realized gains on trading securities	75,000	16,000	151,000
Realized gains on Visa Class B shares	0	463,000	$ 0
Collateral Pledged
Debt Securities, Available-for-sale [Line Items]
Securities pledged to public deposits	$ 453,407,000	$ 405,200,000

Gain (Loss) on Visa Class B Shares

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- Definition

Number of securities holdings.

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No definition available.

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- Definition

Shareholders equity percentage.

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No definition available.

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- Definition

Tax provision related to net realized gains.

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No definition available.

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- Definition

Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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- Definition

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
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- Definition

Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section S99
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- Definition

Cash received from sale of investments in debt and equity securities, classified as operating activities, during the period; includes trading securities and any other investments classified as operating.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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