Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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-Article 12
-Section 13
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The fair value of available-for-sale securities that serve as collateral for borrowings.

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-Publisher FASB
-Name Accounting Standards Codification
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Fair value of all liability derivatives designated as cash flow hedging instruments.

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Fixed interest rate related to the interest rate derivative.

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Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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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Notes Payable and Long-Term Debt (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2010	May 26, 2010	Dec. 31, 2009	Mar. 19, 2009
Debt Instrument [Line Items]
Derivative, Notional Amount				$ 9,000		$ 3,000
Derivative, fixed interest rate				8.49%		7.02%
Cash flow hedge, derivative instrument liabilities at fair value	$ 608	$ 1,030
Unrealized gain on interest rate swap	278	256
Available-for-sale securities pledged as collateral	$ 1,446	1,466
Cash pledged as collateral		$ 231
Interest rate swap
Debt Instrument [Line Items]
Cash flow hedge, liability at fair value					$ 65
Cash flow hedging
Debt Instrument [Line Items]
Cash flow hedge, liability at fair value			$ 543