Note 3 - Supplemental Balance Sheet Information (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Note 3 - Supplemental Balance Sheet Information
Land	$ 123us-gaap_Land	$ 123us-gaap_Land
Buildings and leasehold improvements	7,437us-gaap_BuildingsAndImprovementsGross	7,412us-gaap_BuildingsAndImprovementsGross
Machinery and equipment	48,054us-gaap_MachineryAndEquipmentGross	47,405us-gaap_MachineryAndEquipmentGross
Furniture and fixtures	1,811us-gaap_FurnitureAndFixturesGross	1,866us-gaap_FurnitureAndFixturesGross
Computer hardware and software	4,452us-gaap_PropertyPlantAndEquipmentOther	4,247us-gaap_PropertyPlantAndEquipmentOther
Construction in progress	1,351us-gaap_ConstructionInProgressGross	1,073us-gaap_ConstructionInProgressGross
Total	63,228us-gaap_PropertyPlantAndEquipmentGross	62,126us-gaap_PropertyPlantAndEquipmentGross
Less-Accumulated depreciation	(53,416)	(51,924)
Total	$ 9,812us-gaap_PropertyPlantAndEquipmentNet	$ 10,202us-gaap_PropertyPlantAndEquipmentNet

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

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Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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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.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

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