Stockholders' Equity - Summary of Capital Stock (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Sep. 29, 2020
Class 1 Common Stock [Member]
Class Of Stock [Line Items]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	233,333,333	233,333,333	250,000,000
Common stock voting rights	10 votes for each share
Common Stock Class Two
Class Of Stock [Line Items]
Common stock, par value	$ 0.0001
Common stock, shares authorized	500,000,000
Common stock voting rights	1 vote for each share
Preferred Stock [Member]
Class Of Stock [Line Items]
Convertible preferred stock	$ 0.0001
Convertible preferred stock shares authorized	10,000,000
Convertible preferred stock voting rights	N/A