Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2013

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

Common stock equivalents that could potentially reduce net income per common share in the future that were not included in the determination of diluted loss per common share as their effects were antidilutive are as follows (in thousands):



	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2013	2012	2013	2012
Shares underlying Convertible Senior Notes	28,088	3,969	28,088	1,323
Options to purchase common stock	13,988	11,544	13,929	10,762
Restricted stock units not yet vested and released	1,534	797	1,586	829
Restricted stock awards issued, but unvested	13	7	20	10
Options to purchase shares under the Employee Stock Purchase Plan	136	97	143	89
Warrants to purchase common stock	250	250	250	250
	44,009	16,664	44,016	13,263