Related Party Transactions - Additional Information (Detail) - USD ($)	Aug. 03, 2016	Sep. 30, 2016
Related Party Transaction [Line Items]
Note receivable from affiliate		$ 10,700,000
Unsecured Revolving Demand Promissory \| Valhi Inc
Related Party Transaction [Line Items]
Maximum loan amount	$ 40,000,000
Interest rate on loans repayment	1.00%
Principal due on demand effective date	Dec. 31, 2017
Note receivable from affiliate		$ 10,700,000

Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due after 1 year (or 1 business cycle).

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+ Details