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Loans and ACL (Summary of changes in ACL by segments) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	$ 12,735	$ 13,390	$ 12,895	$ 12,635	$ 13,095	$ 13,108
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, Charge-offs	(172)	(191)
Allowance for loan losses, Recoveries	224	145
Financing Receivable, Credit Loss, Expense (Reversal)	(212)	328
Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	1,239	1,267	1,316			968
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	80	2
Financing Receivable, Credit Loss, Expense (Reversal)	(157)	297
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	5,174	5,903	5,171			5,878
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	2	6
Financing Receivable, Credit Loss, Expense (Reversal)	1	19
Agricultural [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	266	265	287			270
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	0	2
Financing Receivable, Credit Loss, Expense (Reversal)	(21)	(7)
Residential Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	4,600	4,308	4,521			4,336
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, Charge-offs	(1)	(1)
Allowance for loan losses, Recoveries	14	64
Financing Receivable, Credit Loss, Expense (Reversal)	66	(91)
Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest	1,456	1,647	$ 1,600			$ 1,656
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, Charge-offs	(171)	(190)
Allowance for loan losses, Recoveries	128	71
Financing Receivable, Credit Loss, Expense (Reversal)	$ (101)	$ 110

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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