Loans, Major Classifications of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans gross	$ 1,373,477		$ 1,369,445
Allowance for loan losses	5,833	$ 5,530	5,506	$ 5,652	$ 5,679	$ 5,728
Total	1,367,644		1,363,939
Loans and Leases Receivable, Net of Deferred Income	1,373,477		1,369,445
Loans and Leases Receivable, Deferred Income	928		961
Commercial and industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans gross	115,041		101,598
Allowance for loan losses	1,287	1,297	1,095	1,043	957	816
Loans and Leases Receivable, Net of Deferred Income	115,041		101,598
Commercial, secured by real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans gross	903,995		887,679
Allowance for loan losses	3,825	3,494	3,607	3,743	3,634	3,903
Loans and Leases Receivable, Net of Deferred Income	903,995		887,679
Residential real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans gross	316,518		335,106
Allowance for loan losses	625	639	665	697	919	837
Loans and Leases Receivable, Net of Deferred Income	316,518		335,106
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans gross	30,411		34,291
Allowance for loan losses	67	73	105	122	131	153
Loans and Leases Receivable, Net of Deferred Income	30,411		34,291
Agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans gross	7,431		10,649
Allowance for loan losses	18	18	30	37	39	28
Loans and Leases Receivable, Net of Deferred Income	7,431		10,649
Other loans, including deposit overdrafts [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans gross	81		122
Allowance for loan losses	11	$ 9	4	$ 10	$ (1)	$ (9)
Loans and Leases Receivable, Net of Deferred Income	$ 81		$ 122