Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income tax provision	$ 914	$ 536	$ 1,636	$ 1,069
Effective income tax rate	(11.60%)	(4.70%)	(15.40%)	(3.90%)
Potential reduction in unrecognized tax benefit			$ 1,200