Accounts and other receivables, net - Components of Accounts and Other Receivables (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Trade accounts receivable:
VAT and other receivables	$ 29.2	$ 23.9
Refundable income taxes	2.5	2.1
Receivable from affiliates: LPC		29.6
Receivable from affiliates: Contran - income taxes	1.6
Allowance for doubtful accounts	(1.6)	(1.7)
Total	339.0	316.0
Kronos International [Member]
Trade accounts receivable:
Accounts receivable	288.9	247.2
CompX [Member]
Trade accounts receivable:
Accounts receivable	17.5	14.6
WCS [Member]
Trade accounts receivable:
Accounts receivable	$ 0.9	$ 0.3