Warrants - Summary of Warrants Issued to Purchase Common Stock (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Class Of Warrant Or Right [Line Items]
Warrants Exercised during the Year	(30,000)
Warrants Outstanding	5,834,959	5,463,620
January 2021 Placement Agent Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2021-01
Term	5 years 6 months
Exercise Price Per Share	$ 3.99
Warrants Outstanding	393,839
January 2021 Service and Performance Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2021-01
Term	2 years
Exercise Price Per Share	$ 3.08
Warrants Outstanding	7,500
December 2020 Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2020-12
Term	5 years 6 months
Exercise Price Per Share	$ 3.00
Warrants Outstanding	2,618,658	2,618,658
December 2020 Placement Agent Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2020-12
Term	5 years
Exercise Price Per Share	$ 3.82
Warrants Outstanding	130,933	130,933
July 2020 Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2020-07
Term	5 years 6 months
Exercise Price Per Share	$ 3.85
Warrants Outstanding	641,416	641,416
July 2020 Placement Agent Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2020-07
Term	5 years 6 months
Exercise Price Per Share	$ 4.97
Warrants Outstanding	32,071	32,071
May 2020 Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2020-05
Term	5 years
Exercise Price Per Share	$ 4.78
Warrants Outstanding	1,392,345	1,392,345
May 2020 Placement Agent Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2020-05
Term	5 years
Exercise Price Per Share	$ 6.13
Warrants Outstanding	69,617	69,617
March 2020 Service and Performance Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2020-03
Term	3 years
Exercise Price Per Share	$ 2.50
Warrants Outstanding	18,350	18,350
February 12, 2020 Service and Performance Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2020-02
Term	2 years
Exercise Price Per Share	$ 4.71
Warrants Outstanding	150,000	150,000
February 3, 2020 Service and Performance Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2020-02
Term	2 years
Exercise Price Per Share	$ 4.91
Warrants Outstanding	10,000	10,000
September 2019 Placement Agent Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2019-09
Term	5 years
Exercise Price Per Share	$ 9.48
Warrants Outstanding	65,942	65,942
August 2019 Service and Performance Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2019-08
Term	2 years
Exercise Price Per Share	$ 1.92
Warrants Exercised during the Year	(20,000)
Warrants Outstanding		20,000
July 2019 Service and Performance Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2019-07
Term	2 years
Exercise Price Per Share	$ 2.19
Warrants Exercised during the Year	(10,000)
Warrants Outstanding		10,000
June 2019 Placement Agent Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2019-06
Term	5 years
Exercise Price Per Share	$ 6.29
Warrants Outstanding	74,479	74,479
April 2019 Service and Performance Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2019-04
Term	5 years
Exercise Price Per Share	$ 6.18
Warrants Outstanding	145,154	145,154
June 2018 Placement Agent Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2018-06
Term	5 years
Exercise Price Per Share	$ 12.57
Warrants Outstanding	69,617	69,617
March 2018 Placement Agent Warrants [Member]
Class Of Warrant Or Right [Line Items]
Issuance Date	2018-03
Term	5 years
Exercise Price Per Share	$ 41.56
Warrants Outstanding	15,038	15,038