Note 7 - Segment, Significant Customers and Geographic Information - Revenue by Product Family (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue	$ 323,522	$ 259,422	$ 871,294	$ 611,409
DC To DC Products [Member]
Revenue	307,368	247,561	827,605	580,549
Lighting Control Products [Member]
Revenue	$ 16,154	$ 11,861	$ 43,689	$ 30,860

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