Description of the Business and Summary of Significant Accounting Policies (Details 3) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income (Loss) Per Share
Net loss	$ 5,103	$ (1,606)	$ 8,637	$ (1,957)	$ (32,778)	$ (31,780)	$ (22,720)	$ (1,850)	$ 10,177	$ (89,128)	$ (23)
Net Income(loss), shares									48,351	47,256	42,490
Net income (loss) per share	$ 0.11	$ (0.03)	$ 0.18	$ (0.04)	$ (0.69)	$ (0.67)	$ (0.48)	$ (0.04)	$ 0.21	$ (1.89)	$ 0.00
Effect of dilutive common stock equivalents									787		244
Effect of convertible notes									645
Net income (loss)- assuming dilution									$ 10,177	$ (89,128)	$ (23)
Net income (loss)- assuming dilution, shares									49,783	47,256	42,734
Net income (loss)- assuming dilution per share	$ 0.10	$ (0.03)	$ 0.17	$ (0.04)	$ (0.69)	$ (0.67)	$ (0.48)	$ (0.04)	$ 0.20	$ (1.89)	$ 0.00