Note 7 - Segment, Significant Customers and Geographic Information - Revenue by Product Family (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue	$ 259,422	$ 168,813	$ 611,409	$ 461,183
DC To DC Products [Member]
Revenue	247,561	159,723	580,549	432,125
Lighting Control Products [Member]
Revenue	$ 11,861	$ 9,090	$ 30,860	$ 29,058

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