Stockholders' Equity - Additional Information (Details) - USD ($)	1 Months Ended		12 Months Ended
	Apr. 30, 2019	Oct. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Proceeds from issuance of common stock, net			$ 46,277,000	$ 42,974,000
Aggregate offering price			$ 200,000,000.0
Initial Public Offering
Class of Stock [Line Items]
Common stock, shares, issued and sold (in shares)		9,864,666
Common stock, public offering price (in usd per share)		$ 5.00
Proceeds from issuance of common stock, net		$ 43,000,000
April 2019 Offering
Class of Stock [Line Items]
Common stock, shares, issued and sold (in shares)	4,124,475
Common stock, public offering price (in usd per share)	$ 12.00
Proceeds from issuance of common stock, net	$ 46,300,000
Common Stock
Class of Stock [Line Items]
Redeemable convertible preferred stock converted to aggregate of common stock (in shares)				13,225,048
Common stock, shares, issued and sold (in shares)			4,124,475	9,864,666
Common Stock | Initial Public Offering
Class of Stock [Line Items]
Redeemable convertible preferred stock converted to aggregate of common stock (in shares)		13,225,048
Equity Distribution Agreement with Citigroup Global Markets Inc. and William Blair & Company, L.L.C.
Class of Stock [Line Items]
Aggregate offering price			$ 60,000,000