Warrants - Additional Information (Details) - USD ($)			3 Months Ended		6 Months Ended
	May 11, 2015	Jan. 15, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2016	Dec. 31, 2015	Aug. 22, 2014
Class Of Warrant Or Right [Line Items]
Proceeds from exercise of warrants						$ 8,948
Loss on change in fair value of the preferred stock and convertible note warrants			$ 0	$ 628,643	$ 0	$ 239,683
Fair value of the preferred stock warrant liability			$ 0		$ 0			$ 0
Series E Redeemable Convertible Preferred Stock
Class Of Warrant Or Right [Line Items]
Warrants issued to acquire shares	23,396						5,317		2,512,562
Warrants exercise price	$ 23.51		$ 23.51		$ 23.51		$ 23.51		$ 0.2189
Warrant Expiration Date					Aug. 22, 2024
Series C-1 Redeemable Convertible Preferred Stock
Class Of Warrant Or Right [Line Items]
Preferred stock warrants forfeited and cancelled	1,290,350
Series C-2 Redeemable Convertible Preferred Stock | IPO
Class Of Warrant Or Right [Line Items]
Warrants issued to acquire shares	1,488
Warrants exercise price	$ 24.23
Series D Redeemable Convertible Preferred Stock
Class Of Warrant Or Right [Line Items]
Conversion of stock, shares issued	6,729
Proceeds from exercise of warrants	$ 1,752
Common Stock Warrants one
Class Of Warrant Or Right [Line Items]
Warrants issued to acquire shares							45,307
Warrants exercise price			2.76		$ 2.76		$ 2.759
Convertible Note Warrants
Class Of Warrant Or Right [Line Items]
Warrants issued to acquire shares		9,311,586
Warrants exercise price		$ 0.2189	$ 14.00		$ 14.00
Warrant Expiration Date					Jan. 15, 2022
Aggregate consideration		$ 1,354
Convertible Note Warrants | IPO
Class Of Warrant Or Right [Line Items]
Warrants issued to acquire shares	144,772
Warrants exercise price	$ 14.00