Note 17 - Geographic Information - Revenue Information by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenue, net	$ 40,467	$ 52,719
UNITED STATES
Revenue, net	3,761	1,998
TAIWAN, PROVINCE OF CHINA
Revenue, net	23,514	24,020
CHINA
Revenue, net	$ 13,192	$ 26,701

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details