Company's Deferred Tax Assets, Net of Deferred Tax Liabilities and Valuation Allowance (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Deferred tax assets, net of deferred tax liabilities	$ 35,651	$ 21,513
Valuation allowance	(2,138)	(2,130)
Deferred tax assets, net of deferred tax liabilities and valuation allowance	$ 33,513	$ 19,383