Net Income (Loss) Per Share (Computation Of Basic And Diluted Net Income (Loss) Per Share) (Details) (USD $) In Thousands, except Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Net Income (Loss) Per Share [Abstract]
Net income (loss)	$ 5,361	$ 1,182	$ 32,255	$ (1,386)
Weighted average common stock outstanding (basic)	41,396,431	40,404,126	41,146,197	40,246,374
Common equivalent shares from options to purchase common stock, restricted common stock units and performance stock units	1,100,936	950,554	1,220,664
Weighted average common stock outstanding (diluted)	42,497,367	41,354,680	42,366,861	40,246,374
Basic net income (loss) per share	$ 0.13	$ 0.03	$ 0.78	$ (0.03)
Diluted net income (loss) per share	$ 0.13	$ 0.03	$ 0.76	$ (0.03)