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Loans and ALLL (Credit quality indicators for commercial and agricultural credit exposures) (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Total | $ 1,264,173 | $ 1,301,037
Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 740,920 | 807,439
Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 574,660 | 570,587
Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 166,260 | 164,851
Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 72,001
Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 104,314 | 93,955
Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 72,331 | 66,144
Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 31,983 | 27,811
Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 845,234 | 901,394
1 - Excellent [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 300
1 - Excellent [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 300
1 - Excellent [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
1 - Excellent [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 300
2 - High quality [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 13,578 | 15,891
2 - High quality [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 9,045 | 9,010
2 - High quality [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 4,533 | 6,881
2 - High quality [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
2 - High quality [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 442 | 453
2 - High quality [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 342 | 453
2 - High quality [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 100 | 0
2 - High quality [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 14,020 | 16,344
3 - High satisfactory [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 104,741 | 204,223
3 - High satisfactory [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 68,133 | 86,135
3 - High satisfactory [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 36,608 | 46,087
3 - High satisfactory [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 72,001
3 - High satisfactory [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 14,365 | 13,656
3 - High satisfactory [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 9,757 | 9,361
3 - High satisfactory [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 4,608 | 4,295
3 - High satisfactory [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 119,106 | 217,879
4 - Low satisfactory [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 585,574 | 552,864
4 - Low satisfactory [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 471,009 | 448,489
4 - Low satisfactory [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 114,565 | 104,375
4 - Low satisfactory [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
4 - Low satisfactory [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 64,801 | 52,469
4 - Low satisfactory [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 43,587 | 36,483
4 - Low satisfactory [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 21,214 | 15,986
4 - Low satisfactory [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 650,375 | 605,333
5 - Special mention [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 28,217 | 14,563
5 - Special mention [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 20,770 | 13,212
5 - Special mention [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 7,447 | 1,351
5 - Special mention [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
5 - Special mention [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 16,896 | 16,548
5 - Special mention [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 12,262 | 13,096
5 - Special mention [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 4,634 | 3,452
5 - Special mention [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 45,113 | 31,111
6 - Substandard [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 8,714 | 19,257
6 - Substandard [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 5,629 | 13,519
6 - Substandard [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 3,085 | 5,738
6 - Substandard [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
6 - Substandard [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 7,576 | 10,055
6 - Substandard [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 6,316 | 6,252
6 - Substandard [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 1,260 | 3,803
6 - Substandard [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 16,290 | 29,312
7 - Vulnerable [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 96 | 341
7 - Vulnerable [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 74 | 222
7 - Vulnerable [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 22 | 119
7 - Vulnerable [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
7 - Vulnerable [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 234 | 774
7 - Vulnerable [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 67 | 499
7 - Vulnerable [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 167 | 275
7 - Vulnerable [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 330 | 1,115
8 - Doubtful [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
8 - Doubtful [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
Loss [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
Loss [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
Loss [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
Loss [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
Loss [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
Loss [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
Loss [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 0
Loss [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | $ 0 | $ 0

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