Long-Term Debt - Revolving Credit Facility - Additional Information (Detail) (Kronos Worldwide, Inc.) In Millions, unless otherwise specified	12 Months Ended		12 Months Ended			12 Months Ended		12 Months Ended
	Dec. 31, 2014 Foreign Line of Credit Europe EUR (€)	Dec. 31, 2014 Foreign Line of Credit Europe USD ($)	Dec. 31, 2014 Foreign Line of Credit Canada Economic Development Agency Credit Facility USD ($)	Dec. 31, 2014 Foreign Line of Credit Canada Economic Development Agency Credit Facility CAD	Dec. 31, 2012 Foreign Line of Credit Canada Economic Development Agency Credit Facility CAD	Dec. 31, 2014 Revolving North American credit facility USD ($)	Jun. 30, 2012 Revolving North American credit facility USD ($)	Dec. 31, 2014 Revolving North American credit facility Minimum Variable Rate	Dec. 31, 2014 Revolving North American credit facility Minimum Base Rate Option	Dec. 31, 2014 Revolving North American credit facility Maximum Variable Rate	Dec. 31, 2014 Revolving North American credit facility Maximum Base Rate Option	Dec. 31, 2014 Letter Of Credit Revolving North American credit facility USD ($)	Dec. 31, 2014 Canadian Subsidiary Revolving Borrowings Maximum Revolving North American credit facility USD ($)
Line Of Credit Facility [Line Items]
Maximum borrowing capacity	€ 120.0				3.0		$ 125.0					$ 15.0	$ 25.0
Credit facility maturity date	September 2017					June 2017
Debt instrument basis spread on variable rate	1.90%					1.50%		2.00%	1.00%	0.50%
Fixed charge coverage ratio, minimum value											0.011
Revolving credit facility, borrowings			1.5			81.0
Repayment of credit facility						92.1
Percentage of average interest rate, during period						3.75%
Amount available for Borrowing						94.2
Revolving credit facility, borrowings (repayments)	0
Outstanding borrowings under revolving credit facility		0	2.6	7.9
Percentage of borrowings available under credit facility		54.00%
Amount available for borrowing	€ 65.0	$ 79.0