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WARRANTS - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended			6 Months Ended
	Mar. 31, 2018	Jun. 30, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Apr. 19, 2018	Dec. 31, 2017	Dec. 31, 2016
Common Stock Warrants [Line Items]
Preferred stock, shares outstanding (in shares)		0			0		0
Placement warrants not exercised and remained outstanding (in shares)		2,036,733			2,036,733
Change in fair value of warrants		$ 2,055	$ (3,753)		$ 4,885	$ (4,701)
Common Stock
Common Stock Warrants [Line Items]
Issuance of common stock from warrant exercises (in shares)			2,431	42,621
Issuance of common stock upon public offering, net (in shares)				11,856,500
Series A Convertible Preferred Stock
Common Stock Warrants [Line Items]
Preferred stock, shares outstanding (in shares)								0
March 2018 Direct Registered Offering \| Common Stock
Common Stock Warrants [Line Items]
Issuance of common stock upon public offering, net (in shares)	4,090,000
March 2018 Direct Registered Offering \| Series A Convertible Preferred Stock
Common Stock Warrants [Line Items]
Issuance of common stock upon public offering, net (in shares)	3,000,581
Common Stock Warrants \| March 2018 Direct Registered Offering
Common Stock Warrants [Line Items]
Warrants issued (in shares)	1,418,116
Exercise price (in USD per share)	$ 8.31
Proceed from private placement and equity issuances, gross	$ 59,100
Fair value of warrants upon issuance	7,400
Adjustments to additional paid in capital, warrant issued	$ 6,600
2016 Placement Warrants
Common Stock Warrants [Line Items]
Warrants issued (in shares)										1,720,512
Exercise price (in USD per share)		$ 2.95			$ 2.95
Placement warrants not exercised and remained outstanding (in shares)		536,711			536,711
2017 Placement Warrants
Common Stock Warrants [Line Items]
Warrants issued (in shares)									1,380,745
Exercise price (in USD per share)		$ 3.17			$ 3.17
Placement warrants not exercised and remained outstanding (in shares)		1,500,022			1,500,022