Summary of Significant Accounting Policies (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended		111 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012
Calculation of weighted average shares of common stock
Net income (loss) attributed to common stockholders	$ (12,622)	$ 8,183	$ (43,757)	$ (19,119)	$ (304,243)
Basic:
Weighted average common shares used in computing basic net income (loss) per common share	33,369	30,440	31,569	30,329
Basic income (loss) per common share	$ (0.38)	$ 0.27	$ (1.39)	$ (0.63)
Diluted:
Weighted average common shares used in computing basic net income (loss) per common share	33,369	30,440	31,569	30,329
Add: Weighted average stock options		1,158
Add: Weighted average warrants		13
Add: Weighted average ESPP
Add: Weighted average RSUs with time-based vesting
Weighted average common shares used in computing diluted net income (loss) per common share	33,369	31,611	31,569	30,329
Diluted income (loss) per common share	$ (0.38)	$ 0.26	$ (1.39)	$ (0.63)