Common Stock Warrants - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended	9 Months Ended
	Sep. 30, 2020	Jun. 30, 2019	Sep. 30, 2020	Jun. 24, 2019	Mar. 22, 2019	Aug. 31, 2011
Common Stock Warrants [Line Items]
Warrant issued to purchase stock				188,643
Common stock issued for exercise of warrant		19,069	40,357
TriplePoint Capital LLC
Common Stock Warrants [Line Items]
Estimated fair value of warrants					$ 0.6
Series A Redeemable Convertible Preferred Stock
Common Stock Warrants [Line Items]
Estimated fair value of warrants						$ 0.1
Common Stock | TriplePoint Capital LLC
Common Stock Warrants [Line Items]
Warrant issued to purchase stock					65,502
Warrant exercise price per share					$ 9.16
Common stock issued for exercise of warrant	39,415
Common Stock | Series A Redeemable Convertible Preferred Stock
Common Stock Warrants [Line Items]
Warrant issued to purchase stock						188,643
Warrant exercise price per share						$ 0.04
Warrants outstanding	0		0