Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Share-based Compensation, Stock Options, Activity

The following table summarizes stock option activity for 2015 (in thousands, except average prices and weighted average remaining contractual lives):

	Options		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Balance, December 31, 2014	2,841		$	4.95	4.40	$	43
Granted	761		2.23
Exercised	(6	)	0.93
Forfeited	(143	)	3.45
Expired	(487	)	7.66
Balance, December 31, 2015	2,966		$	3.89	4.35	$	442
Options exercisable at December 31, 2015	1,860		$	4.66	3.52	$	41
Options vested as of December 31, 2015 and expected to vest after December 31, 2015	2,881		$	3.93	4.30	$	406

Schedule of Nonvested Share Activity

The following table summarizes non-vested stock activity for 2015:

	Restricted Stock Units				Performance Stock Units
	Restricted Shares		Weighted Average Fair Value		Restricted Shares		Weighted Average Fair Value
Balance, December 31, 2014	128		$	3.78	240		$	3.55
Granted	212		2.21		1,625		2.41
Vested	(166	)	3.08		(113	)	3.55
Forfeited	(23	)	2.79		(127	)	3.55
Balance, December 31, 2015	151		$	2.51	1,625		$	2.41

Schedule of Share-based Compensation, Employee Stock Purchase Plan, Activity

The following table summarizes shares issued under the ESPP (in thousands, except per share amounts):

	Year Ended December 31,
	2015		2014		2013
Shares issued pursuant to the ESPP	175		242		381
Cash received for the purchase of shares pursuant to the ESPP	$	322	$	514	$	767
Weighted average purchase price per share	$	1.84	$	2.12	$	2.01

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The fair value calculations for stock options and ESPP shares used the following assumptions for the years ended December 31:

	Stock Options			ESPP shares
	2015	2014	2013	2015	2014	2013
Share price	$2.06-2.80	$2.50-3.49	$2.98-4.89	$2.15-2.70	$2.15-3.00	$2.55-4.70
Expected life (in years)	4.39-4.41	4.40-4.47	4.43-4.50	1.5	1.5	1.5
Interest rate	1.3-1.6%	1.3-1.5%	0.7-1.3%	0.1-0.7%	0.1-0.5%	0.1-0.3%
Volatility	53.5-54.6%	51.4-52.5%	51.4-71.1%	42.6-55.6%	46.9-55.9%	47.3-55.6%
Dividend yield	—	—	—	—	—	—

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

For the years ended December 31, 2015, 2014 and 2013, stock-based compensation was recognized and allocated in the Consolidated Statements of Operations as follows (in thousands):

	2015		2014		2013
Cost of sales	$	294	$	386	$	550
Research and development	867		818		1,170
Selling, general and administrative	2,791		2,893		3,578
Total stock-based compensation expense	$	3,952	$	4,097	$	5,298