CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Preferred stock, par value (in dollars per share)	$ 0.001
Preferred stock, shares authorized	50,000,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	750,000,000	750,000,000
Common stock, shares issued	40,174,821	32,658,176
Common stock, shares outstanding (in shares)	40,174,821	32,658,176
Series B Preferred Stock
Temporary equity, par value (in dollars per share)	$ 0.001	$ 0.001
Temporary equity, shares authorized	10,000,000	10,000,000
Temporary equity, shares issued	3,604,827	3,427,597
Temporary equity, shares outstanding	3,604,827	3,427,597
Temporary equity, liquidation preference	$ 11,174,964	$ 10,625,551
Preferred stock, shares authorized	10,000,000
Preferred stock, shares issued	3,604,827	3,427,597
Preferred stock, shares outstanding	3,604,827	3,427,597
Series B1 Preferred Stock
Temporary equity, par value (in dollars per share)	$ 0.001	$ 0.001
Temporary equity, shares authorized	17,000,000	17,000,000
Temporary equity, shares issued	10,057,597	13,151,989
Temporary equity, shares outstanding	10,057,597	13,151,989
Temporary equity, liquidation preference	$ 15,689,851	$ 20,517,103
Preferred stock, shares authorized	17,000,000
Preferred stock, shares issued	10,057,597	13,151,989
Preferred stock, shares outstanding	10,057,597	13,151,989
Series A Preferred
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	419,859	453,567
Preferred stock, shares outstanding	419,859	453,567
Preferred stock, liquidation preference	$ 625,590	$ 675,815
Series C Preferred
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	44,000	44,000
Preferred stock, shares issued	0	31,568
Preferred stock, shares outstanding	0	31,568
Preferred stock, liquidation preference	$ 0	$ 3,156,800