Government Grant - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2020
Government Grant [Member]
Grant revenue		$ 0.1	$ 0.4
Accounts Receivable, Related Parties		$ 44,000.0	$ 44,000.0
U.S. Food and Drug Administration [Member]
Grant Received	$ 1.0
Grant Term	2 years