Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Condensed Consolidated Balance Sheets
Convertible preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Convertible preferred, shares authorized	68,360,186	62,200,000
Convertible preferred stock, shares issued	44,967,690	44,967,690
Convertible preferred stock, shares outstanding	44,967,690	44,967,690
Convertible preferred stock, aggregate liquidation preference (in dollars)	$ 58,518	$ 58,518
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized shares	110,000,000	100,000,000
Common stock, issued shares	1,377,659	1,334,115
Common stock, outstanding shares	1,377,659	1,334,115