Stock-Based Compensation - Summary of Share-based Compensation Arrangements by Share-based Payment Award (Detail) - Common Class A [Member]	9 Months Ended
	Sep. 30, 2021 $ / shares
Below $10
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
20 Day VWAP of Class A common stock	$ 10
Percentage of target PSUs	0.00%
$10.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
20 Day VWAP of Class A common stock	$ 10.00
Percentage of target PSUs	25.00%
$12.50
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
20 Day VWAP of Class A common stock	$ 12.50
Percentage of target PSUs	50.00%
$15.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
20 Day VWAP of Class A common stock	$ 15.00
Percentage of target PSUs	100.00%
$18.50
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
20 Day VWAP of Class A common stock	$ 18.50
Percentage of target PSUs	150.00%
$22.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
20 Day VWAP of Class A common stock	$ 22.00
Percentage of target PSUs	200.00%