Note 9 - Segment Information - Segment Income (Loss) Before Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income (loss) before taxes	$ (25)	$ 1,490
Power Supplies [Member]
Income (loss) before taxes	(866)	(153)
Data Storage [Member]
Income (loss) before taxes	$ 841	$ 1,643

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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