Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2014

Summary of the option activity under the Company's Amended and Restated 2000 Stock Option and Equity Incentive Plan (Amended 2000 Plan) and Amended and Restated 2010 Equity Incentive Plan (Amended 2010 Plan), referred to collectively as the "Plans"

A summary of the option activity under the Company’s Amended and Restated 2000 Stock Option and Equity Incentive Plan (Amended 2000 Plan) and Amended and Restated 2010 Equity Incentive Plan (Amended 2010 Plan), referred to collectively as the “Plans,” is presented below (in thousands, except exercise price):

			Options Outstanding
	Available for Grant		Number of Shares		Weighted Average Exercise Prices
Balance at December 31, 2013	422		6,727		$	3.86
Additional shares authorized under the Amended 2010 Plan	500		—		—
Restricted stock units granted	(499	)	—		—
Options granted	(49	)	49		$	4.69
Options cancelled	60		(60	)	$	3.42
Options exercised	—		(300	)	$	3.58
Options expired	(60	)	—		3.42
Balance at March 31, 2014	374		6,416		$	3.89
Additional shares authorized under the Amended 2010 Plan	1,500		—		—
Restricted stock units granted	(9	)	—		—
Options cancelled	4		(4	)	$	5.21
Options exercised	—		(52	)	$	1.61
Options expired	(4	)	—		$	5.21
Balance at June 30, 2014	1,865		6,360		$	3.91

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, 2013	3,178		$	4.42
Granted	118		$	5.22
Cancelled	(40	)	$	4.47
Exercised	(32	)	$	3.88
Balance at March 31, 2014	3,224		$	4.46
Granted	125		$	3.87
Exercised	(20	)	$	1.55
Balance at June 30, 2014	3,329		$	4.45

Summary of restricted stock unit activity

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

	Number of Shares		Weighted Average Grant-Date Fair Value
Non-vested shares at December 31, 2013	27		$	4.46
Granted	499		$	4.62
Vested	(122	)	$	4.62
Non-vested shares at March 31, 2014	404		$	4.61
Granted	9		$	4.62
Vested	(5	)	$	4.62
Non-vested shares at June 30, 2014	408		$	4.61

Summary of significant ranges of outstanding and exercisable options

The following table summarizes significant ranges of outstanding and exercisable options as of June 30, 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		Aggregate Intrinsic value		Number Exercisable	Weighted Average Remaining Contractual Life (in Years)	Weighted Average Exercise Price		Aggregate Intrinsic value
$1.50 - $3.23	2,683	2.90	$	2.63	$	1,430	1,807	2.33	$	2.40	$	1,362
$3.24 - $4.20	2,439	4.41	$	3.78	—		1,374	3.77	$	3.76	—
$4.21 - $5.61	3,627	3.80	$	4.90	—		2,625	2.01	$	5.04	—
$5.62 - $6.50	940	2.59	$	5.98	—		764	2.33	$	5.98	—
	9,689	3.58	$	4.09	$	1,430	6,570	2.50	$	4.15	$	1,362

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

	Three Months Ended June 30,		Six Months Ended June 30,
Employee stock options:	2014	2013	2014	2013
Risk-free interest rate	1.6% - 1.7%	0.5% - 0.8%	1.5% – 1.7%	0.5% – 0.8%
Volatility	55.9% – 56.7%	58.0% – 58.3%	55.9% – 57.5%	58.0% – 59.1%
Expected life (years)	4.0-5.0	4.0	4.0-5.0	4.0
Dividend yield	0%	0%	0%	0%