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Loans and ALLL (Credit quality indicators for commercial and agricultural credit exposures) (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 1,264,173
Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	744,440
Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	566,012
Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	178,428
Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	104,985
Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	73,002
Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	31,983
Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	849,425
1 - Excellent [Member] | Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
1 - Excellent [Member] | Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
1 - Excellent [Member] | Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
1 - Excellent [Member] | Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
1 - Excellent [Member] | Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
1 - Excellent [Member] | Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
1 - Excellent [Member] | Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
2 - High quality [Member] | Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	13,578
2 - High quality [Member] | Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	9,045
2 - High quality [Member] | Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,533
2 - High quality [Member] | Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	442
2 - High quality [Member] | Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	342
2 - High quality [Member] | Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	100
2 - High quality [Member] | Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	14,020
3 - High satisfactory [Member] | Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	104,741
3 - High satisfactory [Member] | Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	68,133
3 - High satisfactory [Member] | Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	36,608
3 - High satisfactory [Member] | Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	14,365
3 - High satisfactory [Member] | Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	9,757
3 - High satisfactory [Member] | Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,608
3 - High satisfactory [Member] | Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	119,106
4 - Low satisfactory [Member] | Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	589,094
4 - Low satisfactory [Member] | Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	462,361
4 - Low satisfactory [Member] | Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	126,733
4 - Low satisfactory [Member] | Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	65,472
4 - Low satisfactory [Member] | Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	44,258
4 - Low satisfactory [Member] | Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	21,214
4 - Low satisfactory [Member] | Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	654,566
5 - Special mention [Member] | Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	28,217
5 - Special mention [Member] | Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	20,770
5 - Special mention [Member] | Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	7,447
5 - Special mention [Member] | Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	16,896
5 - Special mention [Member] | Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	12,262
5 - Special mention [Member] | Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	4,634
5 - Special mention [Member] | Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	45,113
6 - Substandard [Member] | Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	8,714
6 - Substandard [Member] | Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	5,629
6 - Substandard [Member] | Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	3,085
6 - Substandard [Member] | Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	7,576
6 - Substandard [Member] | Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	6,316
6 - Substandard [Member] | Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	1,260
6 - Substandard [Member] | Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	16,290
7 - Vulnerable [Member] | Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	96
7 - Vulnerable [Member] | Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	74
7 - Vulnerable [Member] | Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	22
7 - Vulnerable [Member] | Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	234
7 - Vulnerable [Member] | Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	67
7 - Vulnerable [Member] | Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	167
7 - Vulnerable [Member] | Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	330
8 - Doubtful [Member] | Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
8 - Doubtful [Member] | Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
8 - Doubtful [Member] | Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
8 - Doubtful [Member] | Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
8 - Doubtful [Member] | Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
8 - Doubtful [Member] | Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
8 - Doubtful [Member] | Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
9 - Loss | Total commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
9 - Loss | Commercial real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
9 - Loss | Commercial and Industrial Portfolio Segment
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
9 - Loss | Total agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
9 - Loss | Agricultural real estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
9 - Loss | Agricultural other [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	0
9 - Loss | Commercial And Agricultural Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 0

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