Percentage of uncertain tax positions likelihood of being sustained.

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Significant accounting policies.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Amount of income tax refund received from tax jurisdiction.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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Summary of significant accounting policies - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Significant Accounting Policies [Line Items]
Received net refunds for income taxes			$ 300
Income taxes, net	$ 101	$ 127	(300)
Uncertain tax positions	50.00%
Advertising costs	$ 500	500	500
Research, development and certain sales technical support costs	$ 0	$ 0	$ 0
Minimum \| Buildings
Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	15 years
Minimum \| Equipment and Software
Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	3 years
Maximum \| Buildings
Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	40 years
Maximum \| Equipment and Software
Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	20 years
Kronos
Significant Accounting Policies [Line Items]
Parent company ownership interest	31.00%
CompX
Significant Accounting Policies [Line Items]
Parent company ownership interest	87.00%
Percentage of controlling interest owned	13.00%
Parent Company \| Valhi Inc
Significant Accounting Policies [Line Items]
Parent company ownership interest	83.00%
Parent Company \| Valhi Inc \| Contran Corporation
Significant Accounting Policies [Line Items]
Parent company ownership interest	91.00%