Commitments and Contingencies (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
State and political subdivisions
Concentration Risk [Line Items]
Investment in securities issued by state and political subdivisions within the state of Iowa	$ 77,640
Home equity loans
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	86,617	$ 84,869
Credit cards
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	69,245	66,535
Commercial, real estate and home construction
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	201,055	241,983
Commercial lines and real estate purchase loans
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	295,758	308,342
Outstanding letters of credit
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	$ 6,899	$ 6,618

Firm loan commitments and unused portion of lines of credit [Abstract]

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- Definition

Amount of investment in State of Iowa state and political subdivisions debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 310
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481027/954-310-50-2

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- Definition

The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-10

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