Note 9 - Segment Information - Revenue by Primary Geographic Operating Region (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Revenue	$ 13,439	$ 12,229
Power Supplies [Member]
Revenue	5,079	5,927
Data Storage [Member]
Revenue	8,360	6,302
North America [Member]
Revenue	7,900	6,957
North America [Member] | Power Supplies [Member]
Revenue	3,507	3,356
North America [Member] | Data Storage [Member]
Revenue	4,393	3,601
Europe [Member]
Revenue	1,696	1,849
Europe [Member] | Power Supplies [Member]
Revenue	1,118	1,220
Europe [Member] | Data Storage [Member]
Revenue	578	629
Asia Pacific [Member]
Revenue	3,787	3,276
Asia Pacific [Member] | Power Supplies [Member]
Revenue	454	1,351
Asia Pacific [Member] | Data Storage [Member]
Revenue	3,333	1,925
Other Geographic Areas [Member]
Revenue	56	147
Other Geographic Areas [Member] | Power Supplies [Member]
Revenue
Other Geographic Areas [Member] | Data Storage [Member]
Revenue	$ 56	$ 147