Significant Accounting Policies - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2021 USD ($) Segment $ / shares shares	Mar. 31, 2020 USD ($) $ / shares	Dec. 31, 2020 shares	May 31, 2016 shares
Significant Accounting Policies [Line Items]
Common stock, shares issued | shares	34,360,775		26,883,000
Cash proceeds	$ 3,092,000
Non-cash change in fair value of PIPE Warrant liability	2,396,000	$ (2,648,000)
Restricted cash balances	0
Transfers of financial assets from Level 1 to Level 2	0
Transfers of financial assets from Level 2 to Level 1	$ 0
Effective tax rate	0.00%
United States
Significant Accounting Policies [Line Items]
Number of operating segments | Segment	1
Non-US
Significant Accounting Policies [Line Items]
Net assets located outside of the United States	$ 0
PIPE Warrants
Significant Accounting Policies [Line Items]
Warrants exercise price | $ / shares	$ 10.00	$ 10.00
Minimum
Significant Accounting Policies [Line Items]
Marketable securities maturity term	3 months
PIPE Warrants
Significant Accounting Policies [Line Items]
Warrant liability	$ 9,300,000
Non-cash change in fair value of PIPE Warrant liability	$ 2,400,000	$ 2,600,000
PIPE Warrants | Private Placement
Significant Accounting Policies [Line Items]
Common stock, shares issued | shares				1,764,242
Warrants exercisable shares of common stock exercised | shares	80,309
Cash proceeds	$ 800,000
Warrants exercisable shares of common stock outstanding | shares	1,683,933
Offering Warrants
Significant Accounting Policies [Line Items]
Warrants exercise price | $ / shares	$ 12.50	$ 12.50