Note 11 - Segment Information - Segment Income (Loss) Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income (loss) before taxes	$ 49	$ 405	$ 179	$ 1,469
Power Supplies [Member]
Income (loss) before taxes	(141)	164	(497)	181
Data Storage [Member]
Income (loss) before taxes	$ 190	$ 241	$ 676	$ 1,288

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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