Fair Values of Financial Instruments (Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Carrying Amount [Member]
Assets
Cash and cash equivalents	$ 27,341	$ 26,860
Interest-bearing deposits	1,853	993
Loans held for sale	4,577	4,063
Loans	1,167,758	1,157,120
FHLB stock	11,183	10,925
Interest receivable	5,282	4,629
Interest rate swap asset	525	553
Liabilities
Deposits	1,202,034	1,153,382
FHLB advances	217,163	240,591
Other borrowings	4,232	4,189
Interest payable	456	350
Interest rate swap liability	525	553
Portion at Fair Value Measurement [Member]
Assets
Cash and cash equivalents	27,341	26,860
Interest-bearing deposits	1,853	993
Loans held for sale	4,584	4,094
Loans	1,150,005	1,139,450
FHLB stock	11,183	10,925
Interest receivable	5,282	4,629
Interest rate swap asset	525	553
Liabilities
Deposits	1,199,781	1,152,030
FHLB advances	215,326	239,866
Other borrowings	4,300	4,189
Interest payable	456	350
Interest rate swap liability	525	553
Fair Value, Inputs, Level 1 \| Portion at Fair Value Measurement [Member]
Assets
Cash and cash equivalents	27,341	26,860
Interest-bearing deposits	1,853	993
Liabilities
Deposits	830,877	779,577
Fair Value, Inputs, Level 2 \| Portion at Fair Value Measurement [Member]
Assets
Loans held for sale	4,584	4,094
FHLB stock	11,183	10,925
Interest receivable	5,282	4,629
Interest rate swap asset	525	553
Liabilities
FHLB advances	215,326	239,866
Other borrowings	4,300	4,189
Interest payable	456	350
Interest rate swap liability	525	553
Fair Value, Inputs, Level 3 \| Portion at Fair Value Measurement [Member]
Assets
Loans	1,150,005	1,139,450
Liabilities
Deposits	$ 368,904	$ 372,453

Interest-Bearing Deposits with Banks, Fair Value Disclosure

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Interest Payable, Fair Value Disclosure

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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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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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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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Fair value portion of other liabilities.

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