Note 7 - Segment, Significant Customers and Geographic Information - Revenue by Product Family (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Revenue	$ 254,455	$ 165,778
DC To DC Products [Member]
Revenue	241,429	156,875
Lighting Control Products [Member]
Revenue	$ 13,026	$ 8,903

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