Business and Geographic Information - Schedule of Disaggregates Net Sales By Reporting Unit (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation Of Revenue [Line Items]
Total net sales	$ 29,600	$ 29,700	$ 33,700	$ 31,200	$ 27,400	$ 30,000	$ 32,400	$ 28,400	$ 124,243	$ 118,217	$ 112,035
Security Products
Disaggregation Of Revenue [Line Items]
Total net sales									99,328	98,383	96,600
Marine Components
Disaggregation Of Revenue [Line Items]
Total net sales									$ 24,915	$ 19,834	$ 15,435