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Loans and ALLL (Credit quality indicators for commercial and agricultural credit exposures) (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | $ 1,236,151 | $ 1,301,037
Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 730,504 | 807,439
Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 561,959 | 570,587
Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 167,061 | 164,851
Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 1,484 | 72,001
Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 96,850 | 93,955
Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 66,162 | 66,144
Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 30,688 | 27,811
Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 827,354 | 901,394
1 - Excellent [Member] | Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 300 | 300
1 - Excellent [Member] | Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 300 | 300
1 - Excellent [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 300 | 300
2 - High quality [Member] | Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 14,375 | 15,891
2 - High quality [Member] | Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 9,331 | 9,010
2 - High quality [Member] | Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 5,044 | 6,881
2 - High quality [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
2 - High quality [Member] | Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 443 | 453
2 - High quality [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 383 | 453
2 - High quality [Member] | Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 60 | 0
2 - High quality [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 14,818 | 16,344
3 - High satisfactory [Member] | Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 109,576 | 204,223
3 - High satisfactory [Member] | Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 70,779 | 86,135
3 - High satisfactory [Member] | Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 37,313 | 46,087
3 - High satisfactory [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 1,484 | 72,001
3 - High satisfactory [Member] | Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 13,777 | 13,656
3 - High satisfactory [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 9,833 | 9,361
3 - High satisfactory [Member] | Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 3,944 | 4,295
3 - High satisfactory [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 123,353 | 217,879
4 - Low satisfactory [Member] | Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 571,453 | 552,864
4 - Low satisfactory [Member] | Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 457,821 | 448,489
4 - Low satisfactory [Member] | Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 113,632 | 104,375
4 - Low satisfactory [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
4 - Low satisfactory [Member] | Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 59,728 | 52,469
4 - Low satisfactory [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 38,935 | 36,483
4 - Low satisfactory [Member] | Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 20,793 | 15,986
4 - Low satisfactory [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 631,181 | 605,333
5 - Special mention [Member] | Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 25,423 | 14,563
5 - Special mention [Member] | Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 18,255 | 13,212
5 - Special mention [Member] | Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 7,168 | 1,351
5 - Special mention [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
5 - Special mention [Member] | Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 14,950 | 16,548
5 - Special mention [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 10,540 | 13,096
5 - Special mention [Member] | Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 4,410 | 3,452
5 - Special mention [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 40,373 | 31,111
6 - Substandard [Member] | Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 9,199 | 19,257
6 - Substandard [Member] | Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 5,695 | 13,519
6 - Substandard [Member] | Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 3,504 | 5,738
6 - Substandard [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
6 - Substandard [Member] | Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 7,686 | 10,055
6 - Substandard [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 6,373 | 6,252
6 - Substandard [Member] | Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 1,313 | 3,803
6 - Substandard [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 16,885 | 29,312
7 - Vulnerable [Member] | Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 178 | 341
7 - Vulnerable [Member] | Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 78 | 222
7 - Vulnerable [Member] | Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 100 | 119
7 - Vulnerable [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
7 - Vulnerable [Member] | Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 266 | 774
7 - Vulnerable [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 98 | 499
7 - Vulnerable [Member] | Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 168 | 275
7 - Vulnerable [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 444 | 1,115
8 - Doubtful [Member] | Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
Loss [Member] | Total commercial [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
Loss [Member] | Commercial real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
Loss [Member] | Commercial other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
Loss [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
Loss [Member] | Total agricultural [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
Loss [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
Loss [Member] | Agricultural other [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | 0 | 0
Loss [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |
Total | $ 0 | $ 0

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