Investment in Kronos Worldwide, Inc. - Selected Financial Information of Kronos Income Statement (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule Of Equity Method Investments [Line Items]
Net sales	$ 1,732.4	$ 1,976.3	$ 1,943.3
Cost of sales	1,620.2	1,415.9	1,194.9
Income (loss) from operations	(132.6)	359.6	546.5
Net income (loss)	$ (102.0)	$ 218.5	$ 321.0