Warrants - Summary of Key Terms and Activity of Liability Classified Common Stock Warrants (Detail) - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Class Of Warrant Or Right [Line Items]
Warrants Outstanding	5,864,959	5,463,620
January 2021 Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2021-01
Term	5 years 6 months
Exercise Price Per Share	$ 3.13
Warrants Outstanding	3,938,392
September 2019 Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2019-09
Term	5 years 6 months
Exercise Price Per Share	$ 7.52
Warrants Outstanding	659,414	659,414
June 2019 Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2019-06
Term	5 years 6 months
Exercise Price Per Share	$ 5.00
Warrants Outstanding	435,830	435,830
June 2018 Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2018-06
Term	5 years 6 months
Exercise Price Per Share	$ 9.94
Warrants Exercised during the Year		1,392,345
March 2018 Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2018-03
Term	5 years
Exercise Price Per Share	$ 10.73
Warrants Exercised during the Year		641,416
Warrants Outstanding	641,416	641,416
January 2021, September 2019, June 2019, June 2018 and March 2018 Warrants [Member]
Class Of Warrant Or Right [Line Items]
Warrants Exercised during the Year		2,033,761
Warrants Outstanding	5,675,052	1,736,660