Note 4 - Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2020

Notes Tables

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

			Active Markets		Significant Other		Significant
			for Identical Assets		Observable Inputs		Unobservable Inputs
	December 31, 2020		(Level 1)		(Level 2)		(Level 3)		Amortized Cost
Cash equivalents:
Money Market Funds	$	74,522	$	74,522	$	-	$	-	$	74,522
Investments:
U.S. Treasury Bills	$	2,501	$	2,501	$	-	$	-	$	2,524
Other current and long-term liabilities:
Contingent Consideration - Short Term	$	13,090	$	-	$	-	$	13,090	$	-
Contingent Consideration - Long Term		22,320		-		-		22,320		-
Total other current and long-term liabilities	$	35,410	$	-	$	-	$	35,410	$	-

			Active Markets		Significant Other		Significant
			for Identical Assets		Observable Inputs		Unobservable Inputs
	December 31, 2019		(Level 1)		(Level 2)		(Level 3)		Amortized Cost
Cash equivalents:
Money Market Funds	$	48,971	$	48,971	$	-	$	-	$	48,971
Investments:
U.S. Treasury Bills	$	27,480	$	27,480	$	-	$	-	$	27,479

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

	Year Ended
	December 31, 2020
Balance, beginning January 1, 2020	$	-
Additions		69,076
Payments		(5,000	)
Change in fair value		(28,666	)
Balance, ending December 31, 2020	$	35,410