Note 2 - Sale of Subsidiary; Discontinued Operations - Condensed Financial Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Discontinued Operations, Disposed of by Sale [Member] \| Chem Free [Member]
Net sales		$ 2,678	$ 2,902	$ 7,967
Operating income (loss)		446	(3)	682
Net income before income taxes		456	6	708
Income taxes		8	9	20
Net income (loss) from discontinued operations		448	(3)	688
Net income (loss) from discontinued operations		$ 448	$ (3)	$ 688

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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