Loans Receivable and Allowance for Loan Losses (Classes of the Loan Portfolio Summarized by the Aggregate Risk Rating) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	$ 954,859	$ 970,108
Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount		441,425
Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	936,148	943,427
Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	6,869	14,680
Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	11,842	12,001
Summarized by Performance of Individual Credits [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	434,761	442,181
Summarized by Performance of Individual Credits [Member] | Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	434,092
Summarized by Performance of Individual Credits [Member] | Nonperforming [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	669	756
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	597,906	579,104
Commercial Real Estate Loans [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	586,338	566,418
Commercial Real Estate Loans [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	6,302	6,346
Commercial Real Estate Loans [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	5,266	6,340
Agricultural Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	64,245	66,334
Agricultural Real Estate Loans [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	61,415	58,322
Agricultural Real Estate Loans [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	66	5,111
Agricultural Real Estate Loans [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	2,764	2,901
Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	250,872	283,741
Commercial [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	250,388	282,915
Commercial [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	229	437
Commercial [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	255	389
Other Agricultural Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	41,836	40,929
Other Agricultural Loans [Member] | Pass [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	38,007	35,772
Other Agricultural Loans [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	272	2,786
Other Agricultural Loans [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	3,557	2,371
Residential Real Estate Loans [Member] | Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount		262,556
Residential Real Estate Loans [Member] | Summarized by Performance of Individual Credits [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	258,130	263,127
Residential Real Estate Loans [Member] | Summarized by Performance of Individual Credits [Member] | Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	257,644
Residential Real Estate Loans [Member] | Summarized by Performance of Individual Credits [Member] | Nonperforming [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	486	571
Construction Real Estate Loans [Member] | Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount		21,005
Construction Real Estate Loans [Member] | Summarized by Performance of Individual Credits [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	21,839	21,005
Construction Real Estate Loans [Member] | Summarized by Performance of Individual Credits [Member] | Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	21,839
Consumer Loans To Individuals [Member] | Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount		157,864
Consumer Loans To Individuals [Member] | Summarized by Performance of Individual Credits [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	154,792	158,049
Consumer Loans To Individuals [Member] | Summarized by Performance of Individual Credits [Member] | Performing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	154,609
Consumer Loans To Individuals [Member] | Summarized by Performance of Individual Credits [Member] | Nonperforming [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Amount	$ 183	$ 185