Business Segment Information - Schedule of Business Segment Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Net sales:
Total net sales	$ 42,864	$ 34,556	$ 126,589	$ 106,733
Operating income (loss):
Total operating income	5,920	5,131	19,971	16,706
Interest income	558	289	1,109	945
Income before income taxes	6,478	5,420	21,080	17,651
Depreciation and amortization			2,962	2,861
Total capital expenditures			3,008	2,266
Security Products
Net sales:
Total net sales	28,493	25,829	86,911	79,301
Operating income (loss):
Total operating income	4,904	5,529	17,645	16,864
Marine Components
Net sales:
Total net sales	14,371	8,727	39,678	27,432
Operating income (loss):
Total operating income	2,716	1,255	7,449	4,796
Corporate
Operating income (loss):
Total operating income	$ (1,700)	$ (1,653)	$ (5,123)	$ (4,954)