Note 8 - Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2014

Disclosure Text Block [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	Balance as of			Fair value measurements
Description	December 31, 2014			Level 1		Level 2			Level 3
Assets
Cash equivalents
Money market mutual funds	$	2,746		$	2,746		-			-
Short-term marketable securities and time deposits
U.S. GSE securities	$	1,499			-	$	1,499			-
Corporate debt securities	$	7,410			-	$	7,410			-
Long-term marketable securities
U.S. GSE securities	$	19,552			-	$	19,552			-
Corporate debt securities	$	72,717			-	$	72,717			-
Derivative liabilities	$	(618	)		-	$	(618	)		-

	Balance as of		Fair value measurements
Description	December 31, 2013		Level 1		Level 2		Level 3
Assets
Cash equivalents
Money market mutual funds	$	3,762	$	3,762
Short-term marketable securities and time deposits
U.S. GSE securities	$	251			$	251		-
Corporate debt securities	$	10,733			$	10,733		-
Long-term marketable securities
U.S. GSE securities	$	2,831			$	2,831		-
Corporate debt securities	$	87,331			$	87,331		-