Fair Values of Financial Instruments (Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Carrying Amount [Member]
Assets
Cash and cash equivalents	$ 41,069	$ 27,341
Interest-bearing deposits	4,627	1,853
Loans held for sale	3,686	4,577
Loans	1,436,889	1,167,758
FHLB stock	12,820	11,183
Interest receivable	5,809	5,282
Interest rate swap asset	867	525
Liabilities
Deposits	1,540,452	1,202,034
FHLB advances	230,546	217,163
Other borrowings	18,110	4,232
Interest payable	593	456
Interest rate swap liability	867	525
Portion at Fair Value Measurement [Member]
Assets
Cash and cash equivalents	41,069	27,341
Interest-bearing deposits	4,627	1,853
Loans held for sale	3,740	4,584
Loans	1,407,437	1,150,005
FHLB stock	12,820	11,183
Interest receivable	5,809	5,282
Interest rate swap asset	867	525
Liabilities
Deposits	1,534,582	1,199,781
FHLB advances	227,428	215,326
Other borrowings	18,000	4,300
Interest payable	593	456
Interest rate swap liability	867	525
Fair Value, Inputs, Level 1 \| Portion at Fair Value Measurement [Member]
Assets
Cash and cash equivalents	41,069	27,341
Interest-bearing deposits	4,627	1,853
Liabilities
Deposits	1,083,726	830,877
Fair Value, Inputs, Level 2 \| Portion at Fair Value Measurement [Member]
Assets
Loans held for sale	3,740	4,584
FHLB stock	12,820	11,183
Interest receivable	5,809	5,282
Interest rate swap asset	867	525
Liabilities
FHLB advances	227,428	215,326
Other borrowings	18,000	4,300
Interest payable	593	456
Interest rate swap liability	867	525
Fair Value, Inputs, Level 3 \| Portion at Fair Value Measurement [Member]
Assets
Loans	1,407,437	1,150,005
Liabilities
Deposits	450,856	368,904
Interest Rate Swap [Member]
Assets
Interest rate swap asset	867	525
Liabilities
Interest rate swap liability	867	525
Interest Rate Swap [Member] \| Fair Value, Inputs, Level 1
Assets
Interest rate swap asset
Liabilities
Interest rate swap liability
Interest Rate Swap [Member] \| Fair Value, Inputs, Level 2
Assets
Interest rate swap asset	867	525
Liabilities
Interest rate swap liability	$ 867	$ 525

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Interest Payable, Fair Value Disclosure

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Interest Receivable, 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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