Income Taxes - Components of Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Current tax provision	$ 30,459	$ 10,565	$ 22,308
Deferred tax (benefit) expense	(13,571)	16,904	(987)
Total provision for income taxes	$ 16,888	$ 27,469	$ 21,321