Provision for Income Taxes - Provision for Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Expected tax expense, at the U.S. federal statutory income tax rate of 35%			$ 4,016	$ 3,728
Domestic manufacturing credit			(369)	(343)
State income taxes			342	321
Nondeductible expenses and other			19	20
Total income tax expense	$ 1,209	$ 1,210	$ 4,008	$ 3,726