Note 9 - Commitments and Contingencies (Tables)
 12 Months Ended
Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]  
Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block]

2014

          $ 739  

2015

            600  

2016

            567  

2017 and thereafter

            113  

Total

          $ 2,019  
Schedule of Product Warranty Liability [Table Text Block]
   

Year Ended December 31,

 
   

2013

   

2012

   

2011

 

Balance at beginning of period

  $ 331     $ 561     $ 764  

Warranty provision for product sales

    476       917       870  

Settlements made

    (117 )     (675 )     (626 )

Unused warranty provision

    (239 )     (472 )     (447 )

Balance at end of period

  $ 451     $ 331     $ 561