Note 3 - Inventories (Details) - Inventories, Current (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Inventories, Current [Abstract]
Raw materials and purchased parts for assembly	$ 10,034	$ 9,775
Self-manufactured assembly parts and finished products	10,362	10,894
Total	$ 20,396	$ 20,669

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Amount before valuation reserves of merchandise or goods held by the entity that are readily available for sale and items held by the entity which are partially complete or in the process of being readied for sale.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(1),(3))

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ 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 210.5-02.6(a))

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 330

-SubTopic 10

-Section 35

-Paragraph 2

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- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(4),(5))

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