Note 6 - Segment and Geographic Information - Revenue by Region (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Revenue	$ 100,362	$ 84,512
CHINA
Revenue	56,084	52,388
TAIWAN, PROVINCE OF CHINA
Revenue	14,875	8,855
KOREA, REPUBLIC OF
Revenue	8,161	7,093
Europe [Member]
Revenue	7,907	6,985
South East Asia [Member]
Revenue	6,372	4,338
JAPAN
Revenue	4,825	2,650
UNITED STATES
Revenue	2,042	2,146
Other Region [Member]
Revenue	$ 96	$ 57