Note 8 - Equipment Leasing (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Note 8 - Equipment Leasing (Details) [Line Items]
Machinery and Equipment, Gross	4,322us-gaap_MachineryAndEquipmentGross	$ 4,190us-gaap_MachineryAndEquipmentGross
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	3,647	3,530
Equipment Leased to Other Party [Member]
Note 8 - Equipment Leasing (Details) [Line Items]
Machinery and Equipment, Gross	692	561
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	167	138
Operating Leases, Future Minimum Payments Receivable, Current	151
Thermal Products and Mechanical Products [Member]
Note 8 - Equipment Leasing (Details) [Line Items]
Equipment Leased to Customers, Initial Term	6 months

With regard to certain equipment of the Company that is lease to customers under non-cancellable operating leases, represents the initial term that such leases generally have.

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.14)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 14

-Article 5

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- Definition

Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 4

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765

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- Definition

Future rental payments receivable within one year of the balance sheet date under an operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

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