Long-Term Debt - Long-Term Debt (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Other Subsidiary Debt	Dec. 31, 2012 Other Subsidiary Debt	Dec. 31, 2013 Subsidiary Debt	Dec. 31, 2012 Subsidiary Debt	Dec. 31, 2013 VALHI, INC.	Dec. 31, 2012 VALHI, INC.	Dec. 31, 2013 VALHI, INC. Snake River Notes Payable, Other Payables	Dec. 31, 2012 VALHI, INC. Snake River Notes Payable, Other Payables	Dec. 31, 2013 VALHI, INC. Contran	Dec. 31, 2012 VALHI, INC. Contran	Dec. 31, 2013 Kronos Worldwide, Inc. Note Payable Contran	Dec. 31, 2012 Kronos Worldwide, Inc. Note Payable Contran	Dec. 31, 2013 Kronos Worldwide, Inc. Term Loan	Dec. 31, 2012 Kronos Worldwide, Inc. Term Loan	Dec. 31, 2013 Kronos Worldwide, Inc. Revolving North American credit facility	Dec. 31, 2012 Kronos Worldwide, Inc. Revolving North American credit facility	Dec. 31, 2013 Kronos Worldwide, Inc. Revolving European credit facility	Dec. 31, 2012 Kronos Worldwide, Inc. Revolving European credit facility	Dec. 31, 2013 CompX Timet Finance Management Company	Dec. 31, 2012 CompX Timet Finance Management Company	Dec. 31, 2013 WCS	Dec. 31, 2012 WCS	Dec. 31, 2013 WCS Promissory Notes	Dec. 31, 2012 WCS Promissory Notes	Dec. 31, 2013 Tremont Promissory Notes	Dec. 31, 2012 Tremont Promissory Notes	Dec. 31, 2013 BMI Bank note payable	Jan. 31, 2013 BMI Bank note payable	Dec. 31, 2012 BMI Bank note payable	Dec. 31, 2013 Landwell Note payable to the City of Henderson	Dec. 31, 2012 Landwell Note payable to the City of Henderson	May 31, 2012 Landwell Note payable to the City of Henderson
Long-term debt
Debt instrument									$ 250.0	$ 250.0						$ 384.5						$ 18.5					$ 19.1		$ 11.2	$ 11.9		$ 3.1
Debt instrument											206.5	157.6					11.1			13.2
Total Valhi debt							456.5	407.6
Debt instrument													170.0												2.4	7.2						3.1		3.9
Financing capital lease																							68.6	69.9
Other			10.5	9.2
Total subsidiary debt					296.0	502.5
Total debt	752.5	910.1
Less current maturities	10.7	29.6
Total long-term debt	$ 741.8	$ 880.5