Stockholders’ Equity (Deficit) - Warrants outstanding (Details)	Mar. 31, 2020 $ / shares shares
Redeemable Convertible Preferred Stock and Stockholders’ Deficit
Warrants outstanding	88,556
MidCap Credit Facility | Warrants
Redeemable Convertible Preferred Stock and Stockholders’ Deficit
Warrants outstanding	8,379
warrants exercise price | $ / shares	$ 28.65
Notes payable | Warrants
Redeemable Convertible Preferred Stock and Stockholders’ Deficit
Warrants outstanding	15,712
warrants exercise price | $ / shares	$ 28.65
Convertible promissory notes | Warrants
Redeemable Convertible Preferred Stock and Stockholders’ Deficit
Warrants outstanding	64,465
warrants exercise price | $ / shares	$ 28.65