Note 8 - Accounts Payable and Accrued Liabilities (Tables)
12 Months Ended
Dec. 31, 2021
Notes Tables  
Schedule of Accrued Liabilities [Table Text Block]
  

December 31,

 
  

2021

  

2020

 

Patent and legal costs

 $28  $65 

Accrued compensation

  628   563 

Warranty costs

  96   48 

Taxes and other

  72   45 
  $824  $721