Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2012

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

Schedule of Stock-Based Compensation, Activity

Information with respect to the number and weighted average exercise price of stock options under the 2006 Plan and 2010 Plan is summarized as follows (number of shares in thousands):

	Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2011	3,517		$	4.01
Granted	6,698		$	1.94
Exercised	(18	)	$	1.86
Canceled/Forfeited	(296	)	$	3.24
Outstanding at December 31, 2012	9,901		$	2.64	8.8	$	39
Exercisable at December 31, 2012 (1)	3,081		$	3.13	8	$	39
Vested at December 31, 2012	9,423		$	2.66	8.75	$	39

(1) Includes awards with early exercise provisions that permit optionee to exercise unvested options.

Schedule of Share-based Compensation, Additional Information

	Years Ended December 31,
	2012		2011		2010
Stock Options and Restricted Stock Units
Weighted-average grant date fair value	$	1.35	$	2.88	$	11.52
Aggregate intrinsic value of options exercised	$	9,000	$	226,000	$	61,000
Total fair value of shares vested	$	3,564,000	$	2,340,000	$	660,000

Assumptions used in the Black-Scholes Option-Pricing Model

The assumptions used in the Black-Scholes option-pricing model are as follows:

	Year Ended December 31,
	2012	2011	2010
Stock Options and Restricted Stock Units
Risk free interest rate	0.2% to 1.2%	1.2% to 2.6%	1.7% to 2.3%
Expected term	5.0 to 6.1 years	5.1 to 6.1 years	5.0 to 6.1 years
Expected volatility	80.1% to 86.8%	72.3% to 89.7%	90.8% to 96.0%
Expected dividend yield	—%	—%	—%
Employee Stock Purchase Plan
Risk free interest rate	0.1%	0.1%	N/A
Expected term	0.5 to 1.0 years	0.5 to 1.0 years	N/A
Expected volatility	81.5% to 85.7%	75.2% to 77.1%	N/A
Expected dividend yield	—%	—%	N/A

Stock-Based Compensation Expense

The Company recognized stock-based compensation expense as follows (in thousands):

	Year Ended December 31,
	2012		2011		2010
Cost of sales	$	181	$	137	$	105
Research and development	921		768		393
Selling, general and administrative	5,055		3,904		2,009
Total	$	6,157	$	4,809	$	2,507