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Loans and ALLL (Past due and current loans) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing | $ 0 | $ 0
Nonaccrual | 5,313 | 6,535
Total Past Due and Nonaccrual | 9,610 | 11,405
Current | 1,228,701 | 1,175,165
Total | 1,238,311 | 1,186,570
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 | 1,329 | 1,621
Total Past Due and Nonaccrual | 2,148 | 2,477
Current | 754,538 | 698,464
Total | 756,686 | 700,941
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 | 26 | 390
Total Past Due and Nonaccrual | 359 | 559
Current | 505,938 | 509,594
Total | 506,297 | 510,153
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 | 1,303 | 1,231
Total Past Due and Nonaccrual | 1,789 | 1,918
Current | 198,342 | 153,347
Total | 200,131 | 155,265
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
Current | 50,258 | 35,523
Total | 50,258 | 35,523
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 | 3,785 | 4,285
Total Past Due and Nonaccrual | 3,786 | 4,285
Current | 96,675 | 112,635
Total | 100,461 | 116,920
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 | 3,398 | 2,711
Total Past Due and Nonaccrual | 3,398 | 2,711
Current | 67,820 | 77,316
Total | 71,218 | 80,027
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 | 387 | 1,574
Total Past Due and Nonaccrual | 388 | 1,574
Current | 28,855 | 35,319
Total | 29,243 | 36,893
Total residential 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 | 199 | 629
Total Past Due and Nonaccrual | 3,580 | 4,572
Current | 303,963 | 293,997
Total | 307,543 | 298,569
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 | 0 | 0
Nonaccrual | 199 | 557
Total Past Due and Nonaccrual | 3,547 | 4,278
Current | 269,425 | 253,894
Total | 272,972 | 258,172
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 | 25 | 65
Current | 3,791 | 5,766
Total | 3,816 | 5,831
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 | 0 | 72
Total Past Due and Nonaccrual | 8 | 229
Current | 30,747 | 34,337
Total | 30,755 | 34,566
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 | 96 | 71
Current | 73,525 | 70,069
Total | 73,621 | 70,140
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 | 93 | 68
Current | 70,349 | 66,547
Total | 70,442 | 66,615
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 | 3 | 3
Current | 3,176 | 3,522
Total | 3,179 | 3,525
Financing Receivables, 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 4,152 | 4,426
Financing Receivables, 30 to 59 Days Past Due [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 819 | 670
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 333 | 139
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 486 | 531
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 1 | 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 1 | 0
Financing Receivables, 30 to 59 Days Past Due [Member] | Total residential real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 3,236 | 3,685
Financing Receivables, 30 to 59 Days Past Due [Member] | Residential real estate senior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 3,203 | 3,463
Financing Receivables, 30 to 59 Days Past Due [Member] | Residential real estate junior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 25 | 65
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] |  |
Financing Receivable, Recorded Investment, Past Due | 8 | 157
Financing Receivables, 30 to 59 Days Past Due [Member] | Total consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 96 | 71
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer secured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 93 | 68
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer unsecured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 3 | 3
Financing Receivables, 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 145 | 444
Financing Receivables, 60 to 89 Days Past Due [Member] | Total commercial [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 186
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 30
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 156
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Total agricultural [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Agricultural other [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Total residential real estate [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 145 | 258
Financing Receivables, 60 to 89 Days Past Due [Member] | Residential real estate senior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 145 | 258
Financing Receivables, 60 to 89 Days Past Due [Member] | Residential real estate junior liens [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 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] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Total consumer [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer secured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | 0 | 0
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer unsecured [Member] |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |
Financing Receivable, Recorded Investment, Past Due | $ 0 | $ 0

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