Compensation and Other Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2013

Compensation and Other Benefit Plans [Abstract]

A summary of the status of the Company’s stock option plans as of December 31, 2013, 2012, and 2011, and changes during the years ended on those dates is presented below:

	2013					2012					2011
Options:	Shares			Price*		Shares			Price*		Shares			Price*
Outstanding at beginning of year		6,788,383		$	8.99		5,053,435		$	12.55		2,331,450		$	25.36

Granted		1,168,203		$	3.13		2,351,445		$	2.59		2,920,166		$	2.81
Exercised		(589,355	)	$	2.26		(90,252	)	$	1.68		-		$	-
Forfeited, expired or cancelled		(151,190	)	$	17.46		(526,245	)	$	15.84		(198,181	)	$	35.56

Outstanding at end of year		7,216,041		$	8.42		6,788,383		$	8.99		5,053,435		$	12.55

Exercisable at end of year		4,814,926		$	11.14		4,276,834		$	12.42		3,366,807		$	16.33

*	Weighted-average exercise price

Unvested RSU activity

Unvested RSU activity for the year ended December 31, 2013 is summarized below:

	Number of Shares			Weighted- Average Grant- Date Fair Value
Unvested balance at December 31, 2012		1,459,853		$	2.75
Granted		958,385		$	2.96
Vested		(637,034	)	$	2.57
Forfeited		(43,167	)	$	2.08
Unvested balance at December 31, 2013		1,738,037		$	2.73

Weighted average assumptions

The fair value of stock option awards was estimated using the Black-Scholes model with the following weighted average assumptions for the years ended December 31, 2013, 2012, and 2011:

	Year Ended December 31,
	2013			2012			2011
Dividend yield		0	%		0	%		0	%
Expected volatility		92	%		92	%		88	%
Risk-free interest rate		0.89	%		0.82	%		1.48	%
Expected term	5.6 years			5.6 years			5.4 years

Stock-based compensation expense

The following table shows total stock-based compensation expense included in the consolidated statements of comprehensive loss for the years ended December 31, 2013, 2012, and 2011 (in thousands):

	Year Ended December 31,
	2013		2012		2011
Research and development	$	2,358	$	2,391	$	3,672
Selling, general and administrative		2,741		1,893		4,087
Total stock-based compensation expense	$	5,099	$	4,284	$	7,759