Revenue recognition - Schedule of Disaggregation of Net Sales By Reporting Unit (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Disaggregation Of Revenue [Line Items]
Net sales	$ 39,950	$ 33,667	$ 120,588	$ 107,525
Security Products
Disaggregation Of Revenue [Line Items]
Net sales	30,266	26,567	91,179	84,667
Marine Components
Disaggregation Of Revenue [Line Items]
Net sales	$ 9,684	$ 7,100	$ 29,409	$ 22,858

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

NL INDUSTRIES INC 10-Q