Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Convertible preferred stock, shares authorized		135,913,741
Convertible preferred stock, shares issued		17,266,628
Convertible preferred stock, shares outstanding		17,266,628
Preferred stock, par value	$ 0.001
Preferred stock, shares authorized	10,000,000
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	500,000,000	180,000,000
Common stock, shares issued	30,058,105	1,588,701
Common stock, shares outstanding	30,058,105	1,588,701
Convertible Preferred Stock [Member]
Convertible preferred stock, par value		$ 0.001
Convertible preferred stock, shares authorized		1,843,894
Convertible preferred stock, shares issued		224,564
Convertible preferred stock, shares outstanding		224,564
Convertible preferred stock, aggregate liquidation preference		$ 2.5
Redeemable Convertible Preferred Stock [Member]
Convertible preferred stock, par value		$ 0.001
Convertible preferred stock, shares authorized		134,069,847
Convertible preferred stock, shares issued		17,042,064
Convertible preferred stock, shares outstanding		17,042,064
Convertible preferred stock, aggregate liquidation preference		$ 103.5