Related party transactions - Current Receivables and Payables to Affiliates (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Related Party Transaction
Payables to affiliates	$ 791	$ 706
Related Party \| Other - Trade Items
Related Party Transaction
Payables to affiliates	543	513
Related Party \| Income Taxes \| Valhi
Related Party Transaction
Payables to affiliates	$ 248	$ 193

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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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details