Note 16 - Segment and Geographic Information - Revenue by Product Family (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue	$ 844,452	$ 627,921	$ 582,382
DC To DC Products [Member]
Revenue	800,478	589,651	537,512
Lighting Control Products [Member]
Revenue	$ 43,974	$ 38,270	$ 44,870

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