Fair Value Measurements (Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest bearing deposits with banks	$ 35	$ 58
Federal funds sold	1,013
Interest bearing time deposits with banks	3,535	350
Equity securities	1,162
Available for sale securities	138,650	153,824
Restricted investment in FHLB stock	2,170	3,104
Non-interest bearing deposits	123,709	115,911
Interest bearing deposits	406,078	361,757
Long-term debt	15,000	25,000
Other interest bearing liabilities	1,568	1,593
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	14,280	9,839
Interest bearing deposits with banks	35	58
Federal funds sold	1,013
Interest bearing time deposits with banks	3,535	350
Equity securities	1,162
Available for sale securities	138,650	153,824
Restricted investment in FHLB stock	2,170	3,104
Loans, net of allowance for loan losses	415,037	380,965
Mortgage servicing rights	208	225
Accrued interest receivable	1,761	1,582
Non-interest bearing deposits	123,709	115,911
Interest bearing deposits	406,078	361,757
Securities sold under agreements to repurchase	3,759	9,769
Short-term borrowings	593	12,000
Long-term debt	15,000	25,000
Other interest bearing liabilities	1,568	1,593
Accrued interest payable	315	300
Commitments to extend credit
Letters of credit
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	14,280	9,839
Interest bearing deposits with banks	35	58
Federal funds sold	1,013
Interest bearing time deposits with banks	3,510	350
Equity securities	1,162
Available for sale securities	138,650	153,824
Restricted investment in FHLB stock	2,170	3,104
Loans, net of allowance for loan losses	408,456	372,906
Mortgage servicing rights	208	225
Accrued interest receivable	1,761	1,582
Non-interest bearing deposits	123,709	115,911
Interest bearing deposits	404,957	361,468
Securities sold under agreements to repurchase	3,759	9,769
Short-term borrowings	593	12,000
Long-term debt	14,923	24,885
Other interest bearing liabilities	1,569	1,595
Accrued interest payable	315	300
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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No definition available.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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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No definition available.

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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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No definition available.

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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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No definition available.

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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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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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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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For an unclassified balance sheet, this item represents investments in common and preferred stocks and other forms of securities that provide ownership interests in a corporation.

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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 short-term investments classified as other.

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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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