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Organization and basis of presentation - Additional Information (Detail)	Sep. 30, 2012
Nl Industries [Member]
Noncontrolling Interest [Line Items]
Percentage of ownership held by parent company	87.00%
Valhi's [Member]
Noncontrolling Interest [Line Items]
Percentage of ownership held by parent company	83.00%
Contran Corporation [Memeber]
Noncontrolling Interest [Line Items]
Percentage of ownership held by parent company	95.00%

X

- Details

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X

- Definition

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

+ References

No definition available.

+ Details

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