Note 7 - Segment and Geographic Information (Details) - Revenue by Region - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Note 7 - Segment and Geographic Information (Details) - Revenue by Region [Line Items]
Region	$ 91,194	$ 78,335	$ 246,148	$ 206,832
CHINA
Note 7 - Segment and Geographic Information (Details) - Revenue by Region [Line Items]
Region	58,716	51,796	157,968	132,585
TAIWAN, PROVINCE OF CHINA
Note 7 - Segment and Geographic Information (Details) - Revenue by Region [Line Items]
Region	10,352	9,379	31,524	28,080
KOREA, REPUBLIC OF
Note 7 - Segment and Geographic Information (Details) - Revenue by Region [Line Items]
Region	6,019	4,067	15,373	10,693
Europe [Member]
Note 7 - Segment and Geographic Information (Details) - Revenue by Region [Line Items]
Region	5,956	5,212	16,388	14,377
South East Asia [Member]
Note 7 - Segment and Geographic Information (Details) - Revenue by Region [Line Items]
Region	5,764	1,534	12,839	4,955
JAPAN
Note 7 - Segment and Geographic Information (Details) - Revenue by Region [Line Items]
Region	2,633	2,221	6,930	6,075
UNITED STATES
Note 7 - Segment and Geographic Information (Details) - Revenue by Region [Line Items]
Region	1,673	4,079	4,932	9,913
Other Region [Member]
Note 7 - Segment and Geographic Information (Details) - Revenue by Region [Line Items]
Region	$ 81	$ 47	$ 194	$ 154