Stock-Based Compensation (Details Textual) (USD $)	12 Months Ended				12 Months Ended					12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2012 2005 Stock Option [Member]	Dec. 31, 2012 1995 Stock Option Plan [Member]	Dec. 31, 2012 Maximum [Member] 2005 Stock Option [Member]	Oct. 11, 2007 Maximum [Member] 2005 Stock Option [Member]	Jul. 28, 2005 Maximum [Member] 2005 Stock Option [Member]	Dec. 31, 2012 Employee Stock Purchase Plan [Member]	Dec. 31, 2012 Stock Options [Member]	Dec. 31, 2012 Restricted Stock [Member]	Dec. 31, 2011 Restricted Stock [Member]	Dec. 31, 2010 Restricted Stock [Member]	Dec. 31, 2012 Restricted Stock [Member] Minimum [Member] 2005 Stock Option [Member]	Dec. 31, 2012 Restricted Stock [Member] Key Officers and Employee [Member]	Dec. 31, 2012 Restricted Stock [Member] Board of Directors Non Employee [Member]
Stock-Based Compensation (Textual) [Abstract]
1995 Stock option expiry date						May 24, 2005
Stock option expiration period					10 years
Additional shares authorized, percent					2.50%
Number of additional shares authorized					750,000
Percentage of market value										85.00%
Percentage of employee's payroll deductions limited to employee's compensation										10.00%
Maximum Stock value of shares purchased by employees if one thousand shares purchased										$ 25,000
Maximum number of shares that employee can purchase each year										1,000
Weighted average grant-date fair value of stock options granted	$ 0.80	$ 1.16	$ 2.97
Stock options granted	826,000	25,000	20,000
Restricted stock shares granted																1,000,000	40,000
Value of restricted stock granted																2,500,000	100,000
Restricted stock vesting period					4 years		48 months								12 months	48 months	12 months
Stock-based compensation	3,949,000	6,530,000	9,496,000									400,000	1,500,000	2,100,000
Number of shares available for future grants					2,300,000
Maximum number of shares available for issuance under plan								7,000,000	5,000,000	1,000,000
Cash proceeds on stock option exercised	16,000	12,000	7,254,000								16,000
Unrecognized compensation costs related to non-vested awards granted											6,300,000
Exercise of common stock options, shares	32,000	7,000	760,000								32,000
Exercisable, Aggregate intrinsic value	$ 33,000
Stock Based Compensation (Additional Textual) [Abstract]
Options exercisable	1,474,000	2,167,000	2,545,000	2,754,000
Exercisable, weighted average exercise price	$ 10.09	$ 11.03	$ 11.54	$ 10.55