Note 7 - Segment, Significant Customers and Geographic Information - Revenue by Product Family (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenue	$ 186,209	$ 151,007	$ 351,987	$ 292,370
DC To DC Products [Member]
Revenue	176,113	139,691	332,988	272,402
Lighting Control Products [Member]
Revenue	$ 10,096	$ 11,316	$ 18,999	$ 19,968

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