Organization and Basis of Presentation - Additional Information (Detail) (USD $)	3 Months Ended
Mar. 31, 2014	Sep. 30, 2014
Organization And Basis Of Presentation [Line Items]
Equity method ownership percentage of Kronos Worldwide, Inc		30.00%
Minimum ownership required to designate board member		5.00%
Dividend paid	$ 0
Valhi, Inc
Organization And Basis Of Presentation [Line Items]
Equity method ownership percentage of Kronos Worldwide, Inc		83.00%
Contran Corporation
Organization And Basis Of Presentation [Line Items]
Equity method ownership percentage of Kronos Worldwide, Inc		94.00%

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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

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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- Definition

Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

+ Details

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