Note 4 - Fair Value Measurements

12 Months Ended

Dec. 31, 2020

Notes to Financial Statements

Fair Value Disclosures [Text Block]

4. Fair Value Measurements  

We measure our cash equivalents, restricted cash, and short-term investments at fair value. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. A

three

-tier fair value hierarchy is established as a basis for considering such assumptions and for inputs used in the valuation methodologies in measuring fair value:

Level  1:	Quoted prices in active markets for identical assets or liabilities.
Level  2:	Directly or indirectly observable market-based inputs or unobservable inputs used in models or other valuation methodologies.
Level  3:	Unobservable inputs that are not corroborated by market data. The inputs require significant management judgment or estimation.

We classify our cash equivalents, restricted cash, and short-term investments within Level

1

or Level

2

because our cash equivalents and short-term investments are valued using quoted market prices or alternative pricing sources and models utilizing market observable inputs. We review the pricing techniques and methodologies of the independent pricing service for Level

2

investments and believe that the policies adequately consider market activity, either based on specific transactions for the security valued or based on modeling of securities with similar credit quality, duration, yield and structure that were recently traded.

Assets and liabilities measured at fair value on a recurring basis were as follows (in thousands):

	December 31, 2020
	Quoted Prices in
	Active Markets for		Direct or Indirect
	Identical Assets		Observable
	(Level 1)		Inputs (Level 2)		Total
Assets
Cash equivalents:
Money market funds	$	6,114	$	-	$	6,114
Corporate commercial paper		-		-		-
Corporate debt		-		-		-
Total cash equivalents		6,114		-		6,114
Restricted cash:
Money market funds		337		-		337
Short-term investments:
Corporate commercial paper		-		-		-
Corporate debt		-		-		-
Total short-term investments		-		-		-
Total assets measured at fair value	$	6,451	$	-	$	6,451

	December 31, 2019
	Quoted Prices in
	Active Markets for		Direct or Indirect
	Identical Assets		Observable
	(Level 1)		Inputs (Level 2)		Total
Assets
Cash equivalents:
Money market funds	$	1,871	$	-	$	1,871
Corporate commercial paper		-		999		999
Corporate debt		-		750		750
Total cash equivalents		1,871		1,749		3,620
Restricted cash:
Money market funds		600		-		600
Short-term investments:
Corporate commercial paper		-		748		748
Corporate debt		-		1,501		1,501
Total short-term investments		-		2,249		2,249
Total assets measured at fair value	$	2,471	$	3,998	$	6,469

As of

December 31, 2020

and

2019

, contractual maturities of our short-term investments were less than

one

year, and gross unrealized gains and losses on those investments were

not

material.