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Loans and ALLL (Credit quality indicators for commercial and agricultural credit exposures) (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |
Total | $ 1,301,037 | $ 1,238,311
Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 807,439 | 756,686
Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 570,587 | 506,297
Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 164,851 | 200,131
Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 72,001 | 50,258
Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 93,955 | 100,461
Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 66,144 | 71,218
Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 27,811 | 29,243
Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 901,394 | 857,147
1 - Excellent [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 300 | 0
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 | 300 | 0
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 | 300 | 0
2 - High quality [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 15,891 | 15,714
2 - High quality [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 9,010 | 2,308
2 - High quality [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 6,881 | 13,406
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 | 453 | 552
2 - High quality [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 453 | 541
2 - High quality [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 11
2 - High quality [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 16,344 | 16,266
3 - High satisfactory [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 204,223 | 170,678
3 - High satisfactory [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 86,135 | 69,327
3 - High satisfactory [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 46,087 | 51,093
3 - High satisfactory [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 72,001 | 50,258
3 - High satisfactory [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 13,656 | 19,723
3 - High satisfactory [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 9,361 | 14,411
3 - High satisfactory [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 4,295 | 5,312
3 - High satisfactory [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 217,879 | 190,401
4 - Low satisfactory [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 552,864 | 525,758
4 - Low satisfactory [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 448,489 | 403,733
4 - Low satisfactory [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 104,375 | 122,025
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 | 52,469 | 52,064
4 - Low satisfactory [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 36,483 | 34,464
4 - Low satisfactory [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 15,986 | 17,600
4 - Low satisfactory [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 605,333 | 577,822
5 - Special mention [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 14,563 | 21,223
5 - Special mention [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 13,212 | 15,049
5 - Special mention [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 1,351 | 6,174
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 | 16,548 | 16,377
5 - Special mention [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 13,096 | 13,137
5 - Special mention [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 3,452 | 3,240
5 - Special mention [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 31,111 | 37,600
6 - Substandard [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 19,257 | 21,984
6 - Substandard [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 13,519 | 15,854
6 - Substandard [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 5,738 | 6,130
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 | 10,055 | 7,960
6 - Substandard [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 6,252 | 5,267
6 - Substandard [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 3,803 | 2,693
6 - Substandard [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 29,312 | 29,944
7 - Vulnerable [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 341 | 1,329
7 - Vulnerable [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 222 | 26
7 - Vulnerable [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 119 | 1,303
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 | 774 | 3,595
7 - Vulnerable [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 499 | 3,208
7 - Vulnerable [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 275 | 387
7 - Vulnerable [Member] | Commercial And Agricultural Portfolio Segment [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 1,115 | 4,924
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 | 190
8 - Doubtful [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment [Line Items] |  |
Total | 0 | 190
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 | 190
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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