Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 272	$ 589	$ 548	$ 344
Effective income tax rate	(1.20%)	(2.70%)	(1.60%)	(0.70%)