Commitments and Contingencies (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
State and political subdivisions [Member]
Concentration Risk [Line Items]
Investment in securities issued by state and political subdivisions within the state of Iowa	$ 98,320
Home equity loans [Member]
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	60,782	$ 59,330
Credit cards [Member]
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	54,165	52,802
Commercial, real estate and home construction [Member]
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	100,245	89,171
Commercial lines and real estate purchase loans [Member]
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	178,232	174,637
Outstanding letters of credit [Member]
Firm loan commitments and unused portion of lines of credit [Abstract]
Total financial instrument liabilities with off-balance-sheet risk	$ 8,918	$ 9,033

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.

+ Details

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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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- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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