Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Liability for unrecognized tax benefit, including related estimates of penalties and interest	$ 0	$ 0	$ 0	$ 0
Income tax provision (benefit)	$ 15,000	$ 26,000	$ 49,000	$ 68,000
Projected annual effective tax rate	0.30%	0.20%	0.30%	0.30%
Statutory tax rate			21.00%