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Loans and ACL (Summary of specific reserves by segments) (Details) - Collateral Pledged - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment, Loans	$ 1,168	$ 1,083
Individually evaluated for impairment, ACL	349	84
Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment, Loans	550	465
Individually evaluated for impairment, ACL	275	56
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment, Loans	234	234
Individually evaluated for impairment, ACL	74	28
Agricultural [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment, Loans	167	181
Individually evaluated for impairment, ACL	0	0
Residential Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment, Loans	217	203
Individually evaluated for impairment, ACL	0	0
Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment, Loans	0	0
Individually evaluated for impairment, ACL	$ 0	$ 0

X

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 11B
-Subparagraph (g)
-SubTopic 10
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-11B

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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/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-11C

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L(5)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480418/310-10-S99-4

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