Annual report pursuant to Section 13 and 15(d)

Note 5 - Cash, Cash Equivalents and Investments - Cash Equivalents and Investments Carried at Fair Value (Details)

v3.23.1
Note 5 - Cash, Cash Equivalents and Investments - Cash Equivalents and Investments Carried at Fair Value (Details) - USD ($)
$ in Thousands
Dec. 31, 2022
Dec. 31, 2021
Fair value $ 20,534  
Total 38,152 $ 56,885
Fair Value, Inputs, Level 1 [Member]    
Total 22,087 56,885
Fair Value, Inputs, Level 2 [Member]    
Total 16,065 0
Fair Value, Inputs, Level 3 [Member]    
Total 0 0
Money Market Funds [Member]    
Money market funds, included in cash equivalents 17,618 56,885
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]    
Money market funds, included in cash equivalents 17,618 56,885
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]    
Money market funds, included in cash equivalents 0 0
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]    
Money market funds, included in cash equivalents 0 $ 0
US Treasury Securities [Member]    
Fair value 3,573  
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]    
Fair value 3,573  
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member]    
Fair value 0  
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member]    
Fair value 0  
Debt Security, Government, Non-US [Member]    
Fair value 896  
Debt Security, Government, Non-US [Member] | Fair Value, Inputs, Level 1 [Member]    
Fair value 896  
Debt Security, Government, Non-US [Member] | Fair Value, Inputs, Level 2 [Member]    
Fair value 0  
Debt Security, Government, Non-US [Member] | Fair Value, Inputs, Level 3 [Member]    
Fair value 0  
Asset-Backed Securities [Member]    
Fair value 499  
Asset-Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member]    
Fair value 0  
Asset-Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]    
Fair value 499  
Asset-Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member]    
Fair value 0  
Corporate Bond Securities [Member]    
Fair value 15,566  
Corporate Bond Securities [Member] | Fair Value, Inputs, Level 1 [Member]    
Fair value 0  
Corporate Bond Securities [Member] | Fair Value, Inputs, Level 2 [Member]    
Fair value 15,566  
Corporate Bond Securities [Member] | Fair Value, Inputs, Level 3 [Member]    
Fair value $ 0