The amount of cash paid during the current period to the parent company for taxes on income.

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- Definition

Schedule of significant accounting policies.

+ References

No definition available.

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Significant Accounting Policies [Line Items]
Depreciation	$ 3.7	$ 3.5	$ 3.5
Defined Contribution Plan, Cost Recognized	2.6	2.4	2.3
Income tax payments to NL	$ 4.6	$ 4.7	$ 4.4
Minimum \| Building
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	15 years
Minimum \| Equipment and software
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	3 years
Maximum \| Building
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	40 years
Maximum \| Equipment and software
Schedule Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	20 years
NL Industries
Schedule Of Significant Accounting Policies [Line Items]
Percentage of ownership held by parent company	87.00%
NL Industries \| Valhi Inc
Schedule Of Significant Accounting Policies [Line Items]
Percentage of ownership held by parent company	83.00%
Contran Corporation \| Valhi Inc
Schedule Of Significant Accounting Policies [Line Items]
Percentage of ownership held by parent company	93.00%