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Loans and ALLL (Past due and current loans) (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | $ 0 | $ 0
Nonaccrual | 4,532 | 5,313
Total Past Due and Nonaccrual | 5,863 | 9,610
Current | 1,190,055 | 1,228,701
Total | 1,195,918 | 1,238,311
Total commercial [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 1,328 | 1,329
Total Past Due and Nonaccrual | 1,434 | 2,148
Current | 724,106 | 754,538
Total | 725,540 | 756,686
Commercial real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 46 | 26
Total Past Due and Nonaccrual | 110 | 359
Current | 507,578 | 505,938
Total | 507,688 | 506,297
Commercial other [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 1,282 | 1,303
Total Past Due and Nonaccrual | 1,324 | 1,789
Current | 207,071 | 198,342
Total | 208,395 | 200,131
Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 0 | 0
Current | 9,457 | 50,258
Total | 9,457 | 50,258
Total agricultural [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 3,051 | 3,785
Total Past Due and Nonaccrual | 3,051 | 3,786
Current | 88,578 | 96,675
Total | 91,629 | 100,461
Agricultural real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 2,775 | 3,398
Total Past Due and Nonaccrual | 2,775 | 3,398
Current | 65,097 | 67,820
Total | 67,872 | 71,218
Agricultural other [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 276 | 387
Total Past Due and Nonaccrual | 276 | 388
Current | 23,481 | 28,855
Total | 23,757 | 29,243
Total residential real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 153 | 199
Total Past Due and Nonaccrual | 1,344 | 3,580
Current | 304,565 | 303,963
Total | 305,909 | 307,543
Residential real estate senior liens [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 153 | 199
Total Past Due and Nonaccrual | 1,310 | 3,547
Current | 270,688 | 269,425
Total | 271,998 | 272,972
Residential real estate junior liens [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 0 | 25
Current | 3,533 | 3,791
Total | 3,533 | 3,816
Residential real estate home equity lines of credit [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 34 | 8
Current | 30,344 | 30,747
Total | 30,378 | 30,755
Total Consumer [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 34 | 96
Current | 72,806 | 73,525
Total | 72,840 | 73,621
Consumer secured [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 30 | 93
Current | 69,873 | 70,349
Total | 69,903 | 70,442
Consumer Unsecured Financing Receivable [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 | 0
Nonaccrual | 0 | 0
Total Past Due and Nonaccrual | 4 | 3
Current | 2,933 | 3,176
Total | 2,937 | 3,179
Financial Asset, 30 to 59 Days Past Due [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 1,263 | 4,152
Financial Asset, 30 to 59 Days Past Due [Member] | Total commercial [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 42 | 819
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 333
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial other [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 42 | 486
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Total agricultural [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 1
Financial Asset, 30 to 59 Days Past Due [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Agricultural other [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 1
Financial Asset, 30 to 59 Days Past Due [Member] | Total residential real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 1,187 | 3,236
Financial Asset, 30 to 59 Days Past Due [Member] | Residential real estate senior liens [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 1,153 | 3,203
Financial Asset, 30 to 59 Days Past Due [Member] | Residential real estate junior liens [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 25
Financial Asset, 30 to 59 Days Past Due [Member] | Residential real estate home equity lines of credit [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 34 | 8
Financial Asset, 30 to 59 Days Past Due [Member] | Total Consumer [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 34 | 96
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer secured [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 30 | 93
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer Unsecured Financing Receivable [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 4 | 3
Financial Asset, 60 to 89 Days Past Due [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 68 | 145
Financial Asset, 60 to 89 Days Past Due [Member] | Total commercial [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 64 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 64 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial other [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Advances to Mortgage Brokers Segment [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Total agricultural [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Agricultural real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Agricultural other [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Total residential real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 4 | 145
Financial Asset, 60 to 89 Days Past Due [Member] | Residential real estate senior liens [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 4 | 145
Financial Asset, 60 to 89 Days Past Due [Member] | Residential real estate junior liens [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Residential real estate home equity lines of credit [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Total Consumer [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer secured [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer Unsecured Financing Receivable [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Financing Receivable, Past Due | $ 0 | $ 0

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- Definition Amount of financing receivable 90 days or more past due and still accruing. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919258-210447 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5111-111524 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 80 -URI http://asc.fasb.org/extlink&oid=118955255&loc=SL82922355-210448 + Details
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