Summary of Significant Accounting Policies - Schedule of Allowance for Doubtful Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Doubtful Accounts Receivable [Roll Forward]
Beginning Balance	$ 1,829	$ 1,624	$ 1,478
Additions, net of recoveries	1,997	2,241	740
Less write-offs	(575)	(2,036)	(594)
Ending Balance	$ 3,251	$ 1,829	$ 1,624