Quarterly Results of Operations - Schedule of Quarterly Results of Operations (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net sales	$ 400.1	$ 448.2	$ 516.1	$ 499.2	$ 427.4	$ 508.7	$ 568.4	$ 582.8	$ 1,863.6	$ 2,087.3	$ 2,025.1
Gross margin	55.5	48.6	17.2	12.9	55.3	97.4	162.1	260.4	134.2	575.2	746.7
Operating income (loss)	(4.2)	(42.5)	(46.8)	(45.2)	(2.2)	41.1	103.2	203.3	(138.7)	345.4	521.4
Net income (loss)	10.8	(40.9)	(48.6)	(48.2)	9.2	31.8	61.5	119.6	(126.9)	222.1	295.0
Amounts attributable to Valhi stockholders:
Income (loss) from continuing operations					(12.6)	21.8	43.7	88.5	(98.0)	141.4	214.5
Total discontinued operations, net of tax and noncontrolling interest					16.1	1.2	0.6	0.5		18.4	3.0
Net income (loss) attributable to Valhi stockholders	$ 15.7	$ (34.2)	$ (39.7)	$ (39.8)	$ 3.5	$ 23.0	$ 44.3	$ 89.0	$ (98.0)	$ 159.8	$ 217.5
Earnings per share:
Income (loss) from continuing operations					$ (0.04)	$ 0.06	$ 0.13	$ 0.26	$ (0.29)	$ 0.41	$ 0.63
Income (loss) from discontinued operations					$ 0.05	$ 0.01				$ 0.06	$ 0.01
Net income (loss) per share	$ 0.05	$ (0.10)	$ (0.12)	$ (0.12)	$ 0.01	$ 0.07	$ 0.13	$ 0.26	$ (0.29)	$ 0.47	$ 0.64