Note 14 - Segment and Geographic Information (Tables)
12 Months Ended
Dec. 31, 2014
Segment Reporting [Abstract]  
Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block]
   

Year Ended December 31,

 
   

2014

   

2013

   

2012

 

China

  $ 54,312     $ 23,039     $ 20,724  

United States

    22,918       22,389       21,582  

Korea

    10,123       21,818       17,424  

Other

    68,789       35,418       31,476  
    $ 156,142     $ 102,664     $ 91,206