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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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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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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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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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Significant Accounting Policies [Line Items]
Net income tax payments (received)	$ (1,716,000)	$ 3,109,000	$ 70,000
Uncertain tax positions	50.00%
Advertising costs	$ 0	0	0
Research, development and certain sales technical support costs	0	0	$ 0
Environmental Remediation Litigation
Significant Accounting Policies [Line Items]
Recoveries receivable	$ 15,000,000	$ 0
Minimum \| Building
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 \| Building
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	30.00%
CompX
Significant Accounting Policies [Line Items]
Percentage of controlling interest owned	13.00%
Parent Company \| Valhi Inc
Significant Accounting Policies [Line Items]
Parent company ownership interest	83.00%
Parent Company \| Contran Corporation
Significant Accounting Policies [Line Items]
Parent company ownership interest	92.00%