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Loans and ALLL (Past due and current loans) (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | $ 97 | $ 0
Nonaccrual | 1,245 | 5,313
Total Past Due and Nonaccrual | 4,031 | 9,610
Total | 1,301,037 | 1,238,311
Total commercial [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 341 | 1,329
Total Past Due and Nonaccrual | 561 | 2,148
Total | 807,439 | 756,686
Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 222 | 26
Total Past Due and Nonaccrual | 357 | 359
Total | 570,587 | 506,297
Commercial other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 119 | 1,303
Total Past Due and Nonaccrual | 204 | 1,789
Total | 164,851 | 200,131
Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 0 | 0
Total | 72,001 | 50,258
Total agricultural [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 774 | 3,785
Total Past Due and Nonaccrual | 987 | 3,786
Total | 93,955 | 100,461
Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 499 | 3,398
Total Past Due and Nonaccrual | 712 | 3,398
Total | 66,144 | 71,218
Agricultural other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 275 | 387
Total Past Due and Nonaccrual | 275 | 388
Total | 27,811 | 29,243
Total residential real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 97 | 0
Nonaccrual | 130 | 199
Total Past Due and Nonaccrual | 2,287 | 3,580
Total | 326,361 | 307,543
Residential real estate senior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 97 | 0
Nonaccrual | 93 | 199
Total Past Due and Nonaccrual | 2,243 | 3,547
Total | 293,143 | 272,972
Residential real estate junior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 0 | 25
Total | 2,439 | 3,816
Residential real estate home equity lines of credit [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 37 | 0
Total Past Due and Nonaccrual | 44 | 8
Total | 30,779 | 30,755
Total consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 196 | 96
Total | 73,282 | 73,621
Consumer secured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 186 | 93
Total | 70,445 | 70,442
Consumer unsecured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 10 | 3
Total | 2,837 | 3,179
Financing Receivables, 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 2,652 | 4,152
Financing Receivables, 30 to 59 Days Past Due [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 220 | 819
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 135 | 333
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 85 | 486
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 213 | 1
Financing Receivables, 30 to 59 Days Past Due [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 213 | 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 1
Financing Receivables, 30 to 59 Days Past Due [Member] | Total residential real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 2,023 | 3,236
Financing Receivables, 30 to 59 Days Past Due [Member] | Residential real estate senior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 2,016 | 3,203
Financing Receivables, 30 to 59 Days Past Due [Member] | Residential real estate junior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 25
Financing Receivables, 30 to 59 Days Past Due [Member] | Residential real estate home equity lines of credit [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 7 | 8
Financing Receivables, 30 to 59 Days Past Due [Member] | Total consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 196 | 96
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer secured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 186 | 93
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer unsecured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 10 | 3
Financing Receivables, 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 37 | 145
Financing Receivables, 60 to 89 Days Past Due [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Total residential real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 37 | 145
Financing Receivables, 60 to 89 Days Past Due [Member] | Residential real estate senior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 37 | 145
Financing Receivables, 60 to 89 Days Past Due [Member] | Residential real estate junior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Residential real estate home equity lines of credit [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Total consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer secured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer unsecured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 0 | 0
Financial Asset, Not Past Due |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 1,297,006 | 1,228,701
Financial Asset, Not Past Due | Total commercial [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 806,878 | 754,538
Financial Asset, Not Past Due | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 570,230 | 505,938
Financial Asset, Not Past Due | Commercial other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 164,647 | 198,342
Financial Asset, Not Past Due | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 72,001 | 50,258
Financial Asset, Not Past Due | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 92,968 | 96,675
Financial Asset, Not Past Due | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 65,432 | 67,820
Financial Asset, Not Past Due | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 27,536 | 28,855
Financial Asset, Not Past Due | Total residential real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 324,074 | 303,963
Financial Asset, Not Past Due | Residential real estate senior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 290,900 | 269,425
Financial Asset, Not Past Due | Residential real estate junior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 2,439 | 3,791
Financial Asset, Not Past Due | Residential real estate home equity lines of credit [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 30,735 | 30,747
Financial Asset, Not Past Due | Total consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 73,086 | 73,525
Financial Asset, Not Past Due | Consumer secured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | 70,259 | 70,349
Financial Asset, Not Past Due | Consumer unsecured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Total | $ 2,827 | $ 3,176

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