Long-Term Debt And Lease Liabilities (Schedule Of Long-Term Debt To Unrelated Entities) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Note payable to a financial institution, with interest only payment until maturity
Installment notes bearing interest at the rate of 5.0% to 6.5% per annum collateralized by vehicles with monthly payments including interest, insurance and maintenance of approximately $5		124
Total debt		124
Less current maturities		(51)
Long-term debt, less current maturities		$ 73
Interest rate per annum	6.00%
Periodic payments including interest, insurance and maintenance	$ 5
Maximum [Member]
Debt Instrument [Line Items]
Interest rate per annum	6.50%
Minimum [Member]
Debt Instrument [Line Items]
Interest rate per annum	5.00%

Debt Instrument, Periodic Payments Including Insurance And Maintenance.

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- Definition

Notes Payable, Interest Only Payments Until Maturity

+ References

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-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

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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.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
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-Section S99
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
-SubTopic 10
-Section S99
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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Amount of collateralized debt obligations classified as other.

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