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Loans and ALLL (Summary of information pertaining to TDRs) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	11	18
Pre-Modification Recorded Investment	$ 8,473	$ 8,554
Post-Modification Recorded Investment	$ 8,473	$ 8,554
Commercial other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	5	10
Pre-Modification Recorded Investment	$ 4,761	$ 5,224
Post-Modification Recorded Investment	$ 4,761	$ 5,224
Agricultural other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	6	5
Pre-Modification Recorded Investment	$ 3,712	$ 3,194
Post-Modification Recorded Investment	$ 3,712	$ 3,194
Residential real estate senior liens [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	0	3
Pre-Modification Recorded Investment	$ 0	$ 136
Post-Modification Recorded Investment	$ 0	$ 136
Below Market Interest Rate and Extension of Amortization Period [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	4	16
Pre-Modification Recorded Investment	$ 1,572	$ 7,567
Below Market Interest Rate and Extension of Amortization Period [Member] | Commercial other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	4	8
Pre-Modification Recorded Investment	$ 1,572	$ 4,237
Below Market Interest Rate and Extension of Amortization Period [Member] | Agricultural other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	0	5
Pre-Modification Recorded Investment	$ 0	$ 3,194
Below Market Interest Rate and Extension of Amortization Period [Member] | Residential real estate senior liens [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	0	3
Pre-Modification Recorded Investment	$ 0	$ 136
Interest Rate Below Market Reduction [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	7	2
Pre-Modification Recorded Investment	$ 6,901	$ 987
Interest Rate Below Market Reduction [Member] | Commercial other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	1	2
Pre-Modification Recorded Investment	$ 3,189	$ 987
Interest Rate Below Market Reduction [Member] | Agricultural other [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	6	0
Pre-Modification Recorded Investment	$ 3,712	$ 0
Interest Rate Below Market Reduction [Member] | Residential real estate senior liens [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	0	0
Pre-Modification Recorded Investment	$ 0	$ 0
Principal Forgiveness
Financing Receivable, Modifications [Line Items]
Number of Loans | loan	0	0

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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