Note 2 - Sale of Subsidiary; Discontinued Operations (Details) - Discontinued Operations, Condensed Financial Information (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net loss from discontinued operations	$ (3)	$ (181)
ChemFree [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net sales	2,902	2,564
Operating loss	(3)	(179)
Net income (loss) before income taxes	6	(169)
Income taxes	9	12
Net loss from discontinued operations	$ (3)	$ (181)

Amount before tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal.

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