Related Party Transactions - Additional Information (Detail) - Unsecured Revolving Demand Promissory - Valhi Inc - Subsequent Event	Aug. 03, 2016 USD ($)
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

The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin.

No definition available.

Name:	us-gaap_LoansReceivableBasisSpreadOnVariableRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant