Note 4 - Lease Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Lease term	5 years
Fair Value Inputs, Discount Rate	6.00%
Present value of future lease payments	$ 1,754
Fair value of lease equipment	1,678
Present value of future maintenance exenses	76
Sales	30,508	$ 32,944
Increase (Decrease) in Leasing Receivables	(252)	1,335
Property, Plant and Equipment
Sales		1,678
Deferred Revenue		$ 76
Proceeds from Lease Payments	307
Interest Income, Other	55
Increase (Decrease) in Leasing Receivables	$ 252

Represents the monetary amount of Fair value of lease equipment, as of the indicated date.

No definition available.

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Balance Type:	debit
Period Type:	instant

- Definition

Represents the Lease term, during the indicated time period.

+ References

No definition available.

+ Details

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Namespace Prefix:	fil_
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Balance Type:	na
Period Type:	duration

- Definition

Represents the monetary amount of Present value of future lease payments, as of the indicated date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the monetary amount of Present value of future maintenance exenses, as of the indicated date.

+ References

No definition available.

+ Details

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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 13.A.3)
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-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

The increase (decrease) during the reporting period in the amount due from lessees arising from lease agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount of interest income earned from interest bearing assets classified as other.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of cash inflows from lease payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77888421&loc=SL77919320-209978

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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-URI http://asc.fasb.org/extlink&oid=77888421&loc=SL77919327-209978

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Details

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