Fair Value (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total recorded investment	$ 10,304		$ 9,130
Recorded Investment, with allowance recorded	1,107		491
Impaired Financing Receivable, Related Allowance	174		157
Additional impaired financing receivable	0		1,900
Partially charged down loans			442
Total fair value of impaired loans			1,800
Other real estate owned & other repossessed property	4,993		5,012
OREO	4,800		4,800
Other repossessed property	158		177
Transfers from level 1 to level 2	0
Transfers from level 2 to level 1	0
Brokered deposits	61,598		41,812
Brokered deposits maturing in 2018	4,100
Brokered deposits maturing in 2019	10,900
Brokered deposits maturing in 2020	28,400
Brokered deposits maturing in 2021	13,200
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	199,600		176,600
Stand-by Letters of Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet risks liability amount	3,500		4,600
Estimated Fair Value [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Recorded Investment, with allowance recorded	933		334
Fair value of additional impaired financing receivable recorded investment			1,500
Brokered deposits	60,033		$ 42,304
Other Real Estate Owned [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Amount of write-down recognized on real estate	$ 0	$ 0

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Interest Bearing Domestic Deposit Brokered Maturities Remainder Of Year

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Interest Bearing Domestic Deposit Brokered Maturities Year Four.

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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 investment in impaired financing receivables for which there is a related allowance for credit losses.

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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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