Note 10 - Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2015

Notes Tables

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	For years ended December 31,
	2015		2014		2013
Amortization of restricted stock units	$	3,148	$	4,528	$	6,239
Amortization of ESP Plan		54		44		149
Amortization of stock option awards		6		100		128
Total stock-based compensation	$	3,208	$	4,672	$	6,516
By Financial Statement line item
Cost of sales	$	668	$	861	$	1,041
Research and development expenses		1,339		1,744		2,118
Selling and administrative expenses		1,201		2,067		3,428
Restructuring charges		-		-		(71	)

Schedule of Nonvested Share Activity [Table Text Block]

.	Restricted Stock Units										Stock Options
	Time-based					Performance-based					Time-based
	Units			WA price/ unit		Units			WA price/ unit		Issuable upon exercise			WA exercise price
Outstanding at January 1 , 201 5		2,790		$	1.58		314		$	1.87		1,219		$	4.82
Granted		2,523			1.02		264			1.05		19			0.76
Shares vested/options exercised		(2,743	)		1.36		(37	)		1.99		-			-
Forfeited/expired		(300	)		1.38		(154	)		1.68		(291	)		5.53
Balance at December 31, 201 5		2,270		$	1.24		387		$	1.38		947		$	4.52

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

Range of exercise prices			Outstanding Options at December 31, 2015		Weighted average remaining contractual life		Weighted average exercise price		Exercisable at December 31, 2015		Weighted average exercise price
$0.22	-	$1.93		369		3.3	$	1.87		348	$	1.93
$2.00	-	$3.24		258		5.5	$	3.22		258	$	3.22
$3.65	-	$8.79		58		3.3	$	6.12		58	$	6.12
$8.84	-	$18.98		262		0.9	$	9.19		262	$	9.19

Schedule Of Share Based Payment Award Stock Option Awards And Employee Stock Purchase Plan Valuation Assumptions [Table Text Block]

	Year ended December 31,
	2015			2014			2013
Stock option awards:
Risk-free interest rate		1.3	%		1.7	%		0.8	%
Expected volatility		63	%		58	%		72	%
Average expected term (in years)		5			5			5
Expected dividend yield		0	%		0	%		0	%
Weighted average fair value of options granted	$	0.41		$	0.97		$	1.36
ESP Plan:
Risk-free interest rate		0.7	%		0.3	%		0.1	%
Expected volatility		126	%		72	%		51	%
Average expected term		1			1			1
Expected dividend yield		0	%		0	%		0	%
Weighted average fair value of purchase option	$	0.39		$	0.28		$	0.55
Restricted Stock Units:
Weighted average grant date value, time-based	$	1.02		$	1.48		$	2.12
Weighted average grant date value, performance-based	$	1.05		$	1.84		$	2.02