Stockholders' Equity and Employee Stock Option Plans RSU and RSA activity (Tables)
 12 Months Ended
Dec. 31, 2013
RSU and RSA activity [Abstract]  
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]
The following table provides additional information regarding RSU and RSA activity for the years ended December 31, 2013, 2012, and 2011:
 
 
Number Nonvested and Outstanding

 
Weighted-Average Grant Date Fair-Value

BALANCE AT DECEMBER 31, 2010
 
2,201,169

 
$
8.88

RSUs and RSAs granted
 
1,381,070

 
8.74

RSUs vested and released
 
(580,075
)
 
10.55

RSUs cancelled
 
(480,571
)
 
8.96

BALANCE AT DECEMBER 31, 2011
 
2,521,593

 
$
8.40

RSUs granted
 
700,987

 
3.25

RSUs vested and released
 
(977,149
)
 
8.48

RSUs cancelled
 
(315,817
)
 
7.80

BALANCE AT DECEMBER 31, 2012
 
1,929,614

 
$
6.56

RSUs granted
 
419,056

 
2.34

RSUs vested and released
 
(522,286
)
 
6.99

RSUs cancelled
 
(458,287
)
 
6.19

BALANCE AT DECEMBER 31, 2013
 
1,368,097

 
$
5.22


The fair value of each RSU and RSA granted to employees was estimated on the date of grant by multiplying the number of shares granted times the fair market value of the Company's stock on the grant date.

The total intrinsic value of RSUs and RSAs vested and released during the years ended December 31, 2013, 2012, and 2011 was approximately $1.2 million, $3.7 million, and $5.1 million, respectively. The intrinsic value of vested and released RSUs and RSAs is calculated by multiplying the fair market value of the Company's stock on the vesting date by the number of shares vested. As of December 31, 2013, the number of RSUs and RSAs outstanding and expected to vest was 1,292,436, with a total intrinsic value of $2.8 million. The intrinsic value of the outstanding and expected to vest RSUs and RSAs is calculated based on the market value of the Company's closing stock price of $2.15 as of December 31, 2013, the last market trading day of 2013.