The Company and Nature of Business (Details) $ / shares in Units, $ in Millions			1 Months Ended
	Oct. 16, 2018 USD ($) $ / shares shares	Oct. 04, 2018	Oct. 31, 2018	Dec. 31, 2018 shares	Dec. 31, 2017 shares
Subsidiary, Sale of Stock [Line Items]
Reverse stock split ratio		0.0556	0.0556
Common stock issued upon conversion of redeemable convertible preferred stock (in shares)	12,066,654
Warrants to purchase shares of stock (in shares)					280,876
Adjustments to additional paid-in capital related to warrants | $	$ 1.2
IPO
Subsidiary, Sale of Stock [Line Items]
Number of shares issued in IPO (in shares)	8,280,000
IPO share price (in dollars per share) | $ / shares	$ 15.00
Net proceeds from IPO | $	$ 113.6
Redeemable Convertible Preferred Stock
Subsidiary, Sale of Stock [Line Items]
Warrants to purchase shares of stock (in shares)				0	156,550
Common Stock
Subsidiary, Sale of Stock [Line Items]
Warrants to purchase shares of stock (in shares)	160,657			118,122	124,326
Preferred Stock Warrants | Redeemable Convertible Preferred Stock
Subsidiary, Sale of Stock [Line Items]
Number of warrants converted (in shares)	156,550
Warrants to purchase shares of stock (in shares)					156,550