Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Property and Equipment [Line Items]
Computer software development costs capitalized	$ 13,200	$ 11,700	$ 39,200	$ 32,400
Interest costs incurred	400	400	1,100	1,100
Interest costs capitalized	400	400	1,100	1,100
Retainage amount included in construction in progress	3,400		3,400		$ 3,500
Depreciation and amortization	9,407	7,150	25,503	20,209
Property and Equipment [Member]
Property and Equipment [Line Items]
Depreciation and amortization	$ 16,300	$ 13,800	$ 46,800	$ 39,100