Note 2 - Cash, Cash Equivalents and Marketable Investments (Tables)

6 Months Ended

Jun. 30, 2016

Notes Tables

Unrealized Gain (Loss) on Investments [Table Text Block]

June 30, 2016	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Market Value
Cash and cash equivalents:
Cash	$	5,528	$	—	$	—		$	5,528
Money market funds		1,343		—		—			1,343
Commercial paper		549		—		—			549
Total cash and cash equivalents		7,420		—		—			7,420
Marketable investments:
U.S. government notes		12,218		22		—			12,240
U.S. government agencies		4,027		1		—			4,028
Municipal securities		2,752		6		—			2,758
Commercial paper		5,585		2		—			5,587
Corporate debt securities		11,279		12		(2	)		11,289
Total marketable investments		35,861		43		(2	)		35,902
Total cash, cash equivalents and marketable investments	$	43,281	$	43	$	(2	)	$	43,322

December 31, 2015	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Market Value
Cash and cash equivalents:
Cash	$	9,830	$	—	$	—		$	9,830
Money market funds		1,000		—		—			1,000
Commercial paper		38		—		—			38
Total cash and cash equivalents		10,868		—		—			10,868
Marketable investments:
U.S. government notes		7,780		1		(2	)		7,779
U.S. government agencies		12,630		3		(25	)		12,608
Municipal securities		4,344		2		—			4,346
Commercial paper		4,041		1		(2	)		4,040
Corporate debt securities		8,783		—		(17	)		8,766
Total marketable investments		37,578		7		(46	)		37,539
Total cash, cash equivalents and marketable investments	$	48,446	$	7	$	(46	)	$	48,407

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amount
Due in less than one year	$	28,623
Due in 1 to 3 years		7,279
Total marketable investments	$	35,902