Share-Based Payment Arrangements (Tables)

12 Months Ended

Dec. 31, 2013

Share-Based Payment Arrangements [Abstract]

Assumptions used in computing the fair value of option grants

Under ASC 718 Compensation – Stock Compensation, the fair value of each non-qualified stock option award is estimated on the date of grant using the Black-Scholes option pricing model, which requires input assumptions noted in the following table. Ranges of assumptions for inputs are disclosed where the value of such assumptions varied during the related period. Historical volatilities are based upon daily quoted market prices of our common stock on The NASDAQ Stock Market LLC over a period equal to the expected term of the related equity instruments. We rely only on historical volatility since it provides the most reliable indication of future volatility. Future volatility is expected to be consistent with historical; historical volatility is calculated using a simple average calculation; historical data is available for the length of the option's expected term and a sufficient number of price observations are used consistently. Since our stock options are not traded on a public market, we do not use implied volatility. For 2013, 2012 and 2011 our expected term was calculated based upon historical data related to exercise and post-termination cancellation activity; accordingly, for grants issued to employees and directors and officers (excluding our former CEO in 2011), we are using expected terms of 5.3 and 7.4 years, 5.4 and 7.4 years and 5.3 and 7.4 years, respectively. The expected term of stock options granted to our former CEO in 2011 was calculated separately from stock options granted to employees and directors and officers, and was 8 years for 2011. The expected term for options granted to non-employees was also calculated separately from stock options granted to employees and directors and officers and was ten years, which is the contractual term of those options. We have never paid dividends and do not expect to pay dividends in the future. Therefore, our dividend rate is zero. The risk-free rate for periods within the expected term of the options is based on the U.S. Treasury yield curve in effect at the time of grant. The following table presents assumptions used in computing the fair value of option grants during 2013, 2012 and 2011:

	2013			2012			2011
Expected volatility		73% – 90	%		70% – 85	%		68% – 78	%
Expected dividends	Zero			Zero			Zero
Expected term (years)		5.3 – 10			5.3 – 10			5.3 – 10
Weighted average expected term (years)		5.96			6.11			6.17
Risk-free rate		0.76% – 2.83	%		0.57% – 1.71	%		0.77% – 2.97	%

Summary of option activity under the Plans

A summary of option activity under the Plans as of December 31, 2013 and changes during the year then ended is presented below:

Options	Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Yr.)		Aggregate Intrinsic Value
Outstanding at January 1, 2013		5,366		$	12.27
Granted		1,018			5.13
Exercised		(14	)		5.08
Forfeited		(608	)		10.63
Expired		(463	)		14.70
Outstanding at December 31, 2013		5,299			10.89		5.82	$	304
Exercisable at December 31, 2013		3,875		$	12.45		4.86	$	118

Status of outstanding restricted stock awarded

A summary of the status of our outstanding restricted stock awarded under the Plans as of December 31, 2013 and changes during the year then ended is presented below:

Restricted Stock Awards	Shares			Weighted Average Grant-Date Fair Value
Nonvested at January 1, 2013		28		$	5.35
Granted		-			-
Vested		(27	)		5.35
Forfeited		(1	)		5.35
Nonvested at December 31, 2013		-		$	-

Assumption used for shares purchased under Purchase Plans

The fair value of shares purchased under the Purchase Plans was estimated on the date of grant in accordance with ASC 718 Compensation – Stock Compensation, via the same option valuation model used for options granted under the Plans, but with the following assumptions during 2011:

	2011
Expected volatility		43% – 51	%
Expected dividends	zero
Expected term	6 months
Risk-free rate		0.06% – 0.22	%

Purchases of common stock under the Purchase Plans

Purchases of common stock under the Purchase Plans during 2011 are summarized as follows:

	Qualified Plan						Non-Qualified Plan
	Shares Purchased		Price Range		Weighted Average Grant-Date Fair Value		Shares Purchased		Price Range		Weighted Average Grant-Date Fair Value
2011		428	$	4.62 – $5.65	$	0.88		162	$	4.62 – $5.65	$	0.84

Compensation expense of shares, granted to both employees and non-employees

The total compensation expense of shares, granted to both employees and non-employees, under all of our share-based payment arrangements that was recognized in operations during 2013, 2012 and 2011 was:

	2013		2012		2011
Recognized as:
Research and Development	$	2,524	$	4,568	$	4,499
General and Administrative		1,022		1,968		1,863
Total	$	3,546	$	6,536	$	6,362