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Nature of Business, Basis of Presentation and Liquidity Risk - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Accounting Policies [Abstract]
Accumulated deficit	$ (86,435)						$ (86,435)		$ (60,434)
Net loss	(6,691)	$ (11,311)	$ (7,999)	$ (3,764)	$ (2,922)	$ (3,320)	(26,001)	$ (10,006)
Cash and cash equivalents	33,312						33,312		$ 35,853
Working capital	$ 31,700						31,700
Net cash used in operating activities							$ 24,222	$ 10,994

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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