Accounts and Other Receivables, Net - Components of Accounts and Other Receivables (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Trade accounts receivable:
VAT and other receivables	$ 42.0	$ 42.2
Refundable income taxes	5.3	18.3
Allowance for doubtful accounts	(1.3)	(1.5)
Total	380.4	302.5
Contran | trade items
Trade accounts receivable:
Receivable from Contran – trade items	0.3	0.3
Kronos Worldwide, Inc.
Trade accounts receivable:
Accounts receivable	317.2	229.7
CompX
Trade accounts receivable:
Accounts receivable	10.9	8.7
WCS
Trade accounts receivable:
Accounts receivable	$ 6.0	$ 4.8