Note 7 - Segment, Significant Customers and Geographic Information - Revenue by Product Family (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenue	$ 165,778	$ 141,363
DC To DC Products [Member]
Revenue	156,875	132,711
Lighting Control Products [Member]
Revenue	$ 8,903	$ 8,652

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details