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Expiration date of voting agreement among the voting stockholders of the private parent company.

+ References

No definition available.

+ Details

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- Definition

Voting stock ownership percentage of all classes of voting stock required to maintain the right to designate one board member under the voting agreement.

+ References

No definition available.

+ Details

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- Definition

Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

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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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- Details

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Organization and Basis of Presentation - Additional Information (Detail)	3 Months Ended	1 Months Ended
	Mar. 31, 2015	Feb. 28, 2014	Mar. 31, 2014
Contran Corporation
Basis Of Presentation And Significant Accounting Policies [Line Items]
Voting agreement expiration date	2017-02
Common stock voting rights	Under a voting agreement entered into by all of the voting stockholders of Contran, effective in February 2014 and as amended, the size of the board of directors of Contran was fixed at five members, Ms. Lisa Simmons, Ms. Connelly and Ms. Annette Simmons (and in the event of their death, their heirs) each has the right to designate one of the five members of the Contran board and the remaining two members of the Contran board must consist of members of Contran management. Ms. Lisa Simmons, Ms. Connelly, and Ms. Annette Simmons each serve as members of the Contran board. The voting agreement expires in February 2017
Contran Corporation \| Valhi Inc
Basis Of Presentation And Significant Accounting Policies [Line Items]
Percentage of ownership held by parent company			93.00%
Contran Corporation \| Minimum
Basis Of Presentation And Significant Accounting Policies [Line Items]
Minimum percentage of voting stock ownership required to designate a board member		5.00%
NL
Basis Of Presentation And Significant Accounting Policies [Line Items]
Percentage of ownership held by parent company	87.00%
NL \| Valhi Inc
Basis Of Presentation And Significant Accounting Policies [Line Items]
Percentage of ownership held by parent company			83.00%