Fair Value Measurements (Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest bearing deposits with banks	$ 2,117	$ 110
Federal funds sold	9,000	729
Interest bearing time deposits with banks	2,700	3,290
Equity securities	1,133	1,118
Restricted investment in bank stock	3,098	2,441
Deposits: Non-interest bearing	123,355	126,057
Deposits: Interest bearing	411,020	395,665
Long-term debt	45,000	15,000
Other interest bearing liabilities	1,596	1,596
Carrying Reported Amount Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	14,431	15,617
Interest bearing deposits with banks	2,117	110
Federal funds sold	9,000	729
Interest bearing time deposits with banks	2,700	3,290
Equity securities	181,152	141,953
Restricted investment in bank stock	3,098	2,441
Loans, net of allowance for loan losses	404,436	414,597
Mortgage servicing rights	190	200
Accrued interest receivable	1,841	1,681
Deposits: Non-interest bearing	123,355	126,057
Deposits: Interest bearing	411,020	395,665
Securities sold under agreements to repurchase	2,857	2,911
Short-term borrowings		11,600
Long-term debt	45,000	15,000
Other interest bearing liabilities	1,596	1,596
Accrued interest payable	450	289
Commitments to extend credit
Letters of credit
Estimate Of Fair Value Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	14,431	15,617
Interest bearing deposits with banks	2,117	110
Federal funds sold	9,000	729
Interest bearing time deposits with banks	2,700	3,290
Equity securities	181,152	141,953
Restricted investment in bank stock	3,098	2,441
Loans, net of allowance for loan losses	405,018	415,195
Mortgage servicing rights	190	200
Accrued interest receivable	1,841	1,681
Deposits: Non-interest bearing	123,355	126,057
Deposits: Interest bearing	413,983	395,226
Securities sold under agreements to repurchase	2,857	2,911
Short-term borrowings		11,600
Long-term debt	45,605	14,958
Other interest bearing liabilities	1,597	1,597
Accrued interest payable	450	289
Commitments to extend credit
Letters of credit

Mortgage servicing rights.

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The aggregate of all domestic and foreign interest-bearing liabilities.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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Fair value portion of short term borrowing where a bank borrows, at the federal funds rate, from another bank and securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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The amount outstanding of funds lent to other depository institutions, securities brokers, or securities dealers in the form of Federal Funds sold; for example, immediately available funds lent under agreements or contracts that mature in one business day or roll over under a continuing contract, regardless of the nature of the transaction or the collateral involved, excluding overnight lending for commercial and industrial purposes. Also include Federal Funds sold under agreements to resell on a gross basis, excluding (1) sales of term Federal Funds, (2) due bills representing purchases of securities or other assets by the reporting bank that have not yet been delivered and similar instruments, (3) resale agreements that mature in more than one business day involving assets other than securities, and (4) yield maintenance dollar repurchase agreements.

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Total amount of interest-bearing domestic deposit liabilities, which may include brokered, retail, demand, checking, notice of withdrawal, money market and other interest-bearing deposits.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of domestic noninterest-bearing deposits held by the entity, which may include demand deposits, checking, brokered and retail deposits.

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Amount of investments classified as other.

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Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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