Fair Value of Financial Instruments (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total recorded investment	$ 8,776		$ 8,604
Recorded Investment, with allowance recorded	367		1,872
Impaired Financing Receivable, Related Allowance	95		334
Additional impaired financing receivable	1,973
Partial charge down loans	442		0
Other real estate owned & other repossessed property	4,916		2,767
OREO	4,800		2,600
Other repossessed assets	81		191
Transfers from level 1 to level 2	0
Transfers from level 2 to level 1	0
Interest-bearing domestic deposit, brokered	41,815		29,286
Brokered deposits maturing in 2018	4,000
Brokered deposits maturing in 2019	5,900
Brokered deposits maturing in 2020	21,900
Brokered deposits maturing in 2021	5,000
Brokered deposits maturing in 2022	5,000
Un-funded Loan Commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks liability amount	164,000		185,800
Stand-by Letters of Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks liability amount	3,400		2,800
Estimated Fair Value [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Recorded Investment, with allowance recorded	1,531		1,500
Interest-bearing domestic deposit, brokered	42,786		$ 28,873
Other Real Estate Owned [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Amount wrote down of carrying value of OREO property		$ 0
One OREO Property [Member] \| Other Real Estate Owned [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
OREO	817
Amount wrote down of carrying value of OREO property	121
Collateral Dependent Loans [Member] \| Estimated Fair Value [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Recorded Investment, with allowance recorded	$ 272

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Interest Bearing Domestic Deposit Brokered Maturities Year Five.

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Interest Bearing Domestic Deposit Brokered Maturities Year Four.

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Interest Bearing Domestic Deposit Brokered Maturities Year One

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Interest Bearing Domestic Deposit Brokered Maturities Year Three

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Interest Bearing Domestic Deposit Brokered Maturities Year Two

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Partial Charge Down, Financing Receivable

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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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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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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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount of allowance for credit losses related to recorded investment.

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Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

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Carrying amount as of the balance sheet date of assets other than real property that were received in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance.

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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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Amount of write-down or reserve recognized in the income statement on real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

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