Note 3 - Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

	Fair Value Measurements at the End of the Reporting Period
	Level 1		Level 2		Level 3		Total
Items measured at fair value on a recurring basis on December 31, 2021
Cash and cash equivalents
Money market funds	$	-	$	170	$	-	$	170
Short-term investments
Time deposits with original maturity of more than 3 months but less than 12 months	$	29,186	$	-	$	-	$	29,186
Items measured at fair value on a recurring basis on December 31, 2020
Cash and cash equivalents
Money market funds	$	-	$	171	$	-	$	171
Short-term investments
Time deposits with original maturity of more than 3 months but less than 12 months	$	29,054	$	-	$	-	$	29,054