Accounts and Other Receivables, Net - Schedule of Accounts Notes Loans and Financing Receivable (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Receivables [Abstract]
Trade receivables—CompX	$ 10,815	$ 8,696
Promissory note receivable		3,034
Accrued insurance recoveries	1,900	476
Income taxes receivable from Valhi	2,197
Other receivables	127	51
Refundable income taxes	14	8
Allowance for doubtful accounts	(139)	(216)
Total	$ 14,914	$ 12,049