Income Taxes - Schedule of Income Tax Provision (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal	$ 6,234	$ 4,957	$ 3,429
State	388	892	753
Foreign	939	3,191	1,944
Current Income Tax Expense (Benefit), Total	7,561	9,040	6,126
Deferred:
Federal	(2,479)	(2,794)	(3,012)
State	114	(409)	(563)
Foreign	(758)	(547)	87
Deferred income tax expense (benefit)	(3,123)	(3,750)	(3,488)
Income tax provision from continuing operations	$ 4,438	$ 5,290	$ 2,638