Note 2 - Discontinued Operations - Condensed Financial Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Net loss from discontinued operations		$ (3)
Chem Free [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Net sales		2,902
Operating income		197
Net income before income taxes		6
Income taxes		9
Net loss from discontinued operations		$ (3)

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

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Amount of operating income (loss) attributable to disposal group, including, but not limited to, discontinued operation.

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