Warrants - Additional Information (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) Tranche $ / shares shares	Jun. 15, 2015 $ / shares
Class Of Warrant Or Right [Line Items]
Number of tranches | Tranche	2
First tranche
Class Of Warrant Or Right [Line Items]
Common stock warrants outstanding | shares	370,370
Exercise price of common stock warrants		$ 2.70
Common stock warrants life		7 years
Common stock warrants expiration date	Jun. 15, 2022
Warrant
Class Of Warrant Or Right [Line Items]
Fair value of common stock	$ 4.70
Intrinsic value of common stock warrants | $	$ 741,000
Second tranche
Class Of Warrant Or Right [Line Items]
Common stock warrants outstanding | shares	882,071
Exercise price of common stock warrants	$ 9.38
Common stock warrants life	5 years
Common stock warrants expiration date	Dec. 26, 2022