Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Redeemable common stock
Redeemable common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Redeemable common stock, shares issued (in shares)	0	456,043
Redeemable common stock, shares outstanding (in shares)	0	456,043
Common stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	100,000,000	22,080,000
Common stock, shares issued	27,645,108	6,817,093
Common stock, shares outstanding	27,645,108	6,817,093
Class D Preferred Stock
Preferred stock
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	0	3,105,000
Preferred stock, shares issued (in shares)	0	3,093,092
Preferred stock, shares outstanding (in shares)	0	3,093,092
Preferred stock, aggregate liquidation preference (in dollars)		$ 64,999,782
Class C Preferred Stock
Preferred stock
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	0	2,365,020
Preferred stock, shares issued (in shares)	0	2,365,020
Preferred stock, shares outstanding (in shares)	0	2,365,020
Preferred stock, aggregate liquidation preference (in dollars)		$ 5,003,492
Class B-2 Preferred Stock
Preferred stock
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	0	326,557
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Class B-1 Preferred Stock
Preferred stock
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	0	3,278,938
Preferred stock, shares issued (in shares)	0	3,237,528
Preferred stock, shares outstanding (in shares)	0	3,237,528
Preferred stock, aggregate liquidation preference (in dollars)		$ 8,000,003
Undesignated Preferred Stock
Preferred stock
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	10,000,000	1,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

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