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Long-Term Debt (Schedule Of Long-term Debt) (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Line of Credit Facility [Line Items] |  |
Notes payable to a bank, with interest only payment until maturity |  | $ 2,400
Installment notes bearing interest at the rate of 4.16% to 4.6% per annum collateralized by vehicles with monthly payments including interest, insurance and maintenance of approximately $10 | $ 90 | $ 102
Periodic payments including interest, insurance and maintenance | $ 10 |
Maximum [Member] |  |
Line of Credit Facility [Line Items] |  |
Interest rate per annum | 4.60% |
Minimum [Member] |  |
Line of Credit Facility [Line Items] |  |
Interest rate per annum | 4.16% |

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- Definition Notes Payable, Interest Only Payments Until Maturity + References No definition available. + Details
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Balance Type: | credit
Period Type: | instant

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition 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. + References No definition available. + Details
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- Definition Amount of collateralized debt obligations classified as other. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details
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Period Type: | instant

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- Details
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- Details
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