Income Taxes - Schedule of Reconciliation of Uncertain Tax Position (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Reconciliation Of Unrecognized Tax Benefits Excluding Amounts Pertaining To Examined Tax Returns Roll Forward
Balance as of January 1	$ 254	$ 939
Additions for tax positions taken in prior years	2	4
Reductions of tax positions taken in prior years	(117)	(240)
Reductions for settlements on tax positions of prior years		(449)
Balance as of December 31	$ 139	$ 254