Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Schedule of assumptions used in estimation of fair value of the share-based payment awards on the grant date

	Year Ended December 31,
Employee stock options:	2014			2013			2012
Risk-free interest rate		1.3% - 1.7	%		0.5% - 1.7	%		0.2% - 0.8	%
Volatility		53.7% - 57.5	%		57.7% - 62.9	%		59.5% - 73.1	%
Expected life (years)		4.0 - 5.0			4.0 - 5.0			4.0
Dividend yield		0	%		0	%		0	%

Summary of activity under the Plans

A summary of option activity under the Plans is presented below (in thousands, except exercise price):

				Options outstanding
	Shares Available for Grant			Number of Shares			Weighted Average Exercise Prices
Balance at December 31, 2011		1,977			6,528		$	4.48
Additional shares authorized under the Amended 2010 Plan		500			—			—
Options granted		(1,827	)		1,827		$	3.19
Options cancelled		1,217			(1,217	)	$	5.42
Options exercised		—			(266	)	$	2.38
Options expired		(602	)		—		$	6.89

Balance at December 31, 2012		1,265			6,872		$	4.05
Additional shares authorized under the Amended 2010 Plan		500			—			—
Restricted stock units granted		(35	)		—			—
Options granted		(1,543	)		1,543		$	4.27
Options cancelled		1,123			(1,123	)	$	6.00
Options exercised		—			(565	)	$	3.05
Options expired		(888	)		—		$	6.49

Balance at December 31, 2013		422			6,727		$	3.86
Additional shares authorized under the Amended 2010 Plan		2,000			—			—
Restricted stock units granted		(508	)		—			—
Restricted stock units cancelled		5			—			—
Options granted		(174	)		174		$	3.53
Options cancelled		496			(496	)	$	4.31
Options exercised		—			(411	)	$	3.06
Options expired		(481	)		—		$	4.32

Balance at December 31, 2014		1,760			5,994		$	3.87

Summary of the inducement grant option activity

A summary of the inducement grant option activity is presented below (in thousands, except exercise price):

	Options Outstanding
	Number of Shares			Weighted Average Exercise Prices
Balance at December 31, 2011		4,815		$	3.29
Granted		350		$	3.92
Cancelled		(550	)	$	1.55
Exercised		(1,257	)	$	1.55

Balance at December 31, 2012		3,358		$	4.29
Granted		347		$	3.94
Cancelled		(7	)	$	3.45
Exercised		(520	)	$	3.28

Balance at December 31, 2013		3,178		$	4.42
Granted		418		$	3.68
Exercised		(73	)	$	2.59
Expired		(1,290	)	$	5.57

Balance at December 31, 2014		2,233		$	3.68

Summary of restricted stock unit activity

A summary of restricted stock unit activity under the Plans is presented below (in thousands, except fair value):

	Number of Shares			Weighted Average Grant-Date Fair Value
Non-vested shares at December 31, 2011		15		$	1.60
Vested		(12	)	$	1.62
Cancelled		(3	)	$	1.55

Non-vested shares at December 31, 2012		—			—
Granted		35		$	4.46
Vested		(8	)	$	4.46

Non-vested shares at December 31, 2013		27		$	4.46
Granted		508		$	4.61
Vested		(136	)	$	4.60
Cancelled		(5	)	$	4.62

Non-vested shares at December 31, 2014		394		$	4.61

Summary of significant ranges of outstanding and exercisable options

The following table summarizes significant ranges of outstanding and exercisable options as of December 31, 2014 (in thousands, except contractual life and exercise price):

	Options Outstanding						Options Exercisable
Range of Exercise Price	Number Outstanding		Weighted Average Remaining Contractual Life (in Years)		Weighted Average Exercise Price		Number Exercisable		Weighted Average Exercise Price		Aggregate Intrinsic Value
$1.50 - $3.10		2,155		2.60	$	2.48		1,579	$	2.34
$3.11 - $3.85		2,289		4.00	$	3.52		1,541	$	3.57
$3.86 - $4.46		2,241		5.79	$	4.28		1,315	$	4.27
$4.47 - $6.50		1,542		2.88	$	5.47		1,277	$	5.52

$1.50 - $6.50		8,227		3.91	$	3.82		5,712	$	3.83	$	197


Vested and expected to vest		7,981		3.81	$	3.82					$	196


Exercisable		5,712		2.92	$	3.83					$	191