Commitments and Contingencies - Additional Information (Detail) (USD $)				1 Months Ended			6 Months Ended				1 Months Ended	6 Months Ended		3 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Other Environmental Cleanup Matters	Apr. 30, 2014 Collateral Trust Waste Control Specialists	Mar. 31, 2014 Collateral Trust Waste Control Specialists	Jun. 30, 2014 NL Environmental Remediation Sites Nl Named As Prp Or Defendant site	Jun. 30, 2014 NL Lead Pigment Litigation Cases	Jun. 30, 2014 NL California Lead Paint Litigation	Jun. 30, 2014 NL Product Liability And Occupational Exposure Litigation Claims Pending Claims Plaintiff Cases	Jun. 30, 2014 NL Product Liability And Occupational Exposure Litigation Claims Administratively Dismissed Claims Plaintiff	Apr. 30, 2014 Valhi Surety Bond Contran Waste Control Specialists	Jun. 30, 2014 Valhi Surety Bond Contran Waste Control Specialists	Dec. 31, 2013 Valhi Surety Bond Contran Waste Control Specialists	Sep. 30, 2014 Valhi Surety Bond Contran Quarterly Payment Waste Control Specialists Subsequent Event
Commitments And Contingent Liabilities [Line Items]
Number of cases settled and dismissed and found not liable							100
Period by which loss contingency claims settled and dismissed							20 years
Payments for litigation								$ 1,150,000,000
Accrual for reasonably estimable environmental remediation and related matters	126,800,000	122,700,000	8,600,000			118,000,000
Number of sites associated with remediation ad related costs						45
Upper end range, estimate costs for remediation and related matters						158,000,000
Number of sites for which NL not currently able to estimate range of costs						5
Cases pending									1,130
Number of plaintiffs involved									1,643	8,298
Surety bond purchased from third party insurance company											85,300,000		32,200,000
Collateral trust as a percent of value of bonds													2.50%
Cash payments to collateral trust											2,000,000	8,400,000		1,300,000
Restricted cash					18,000,000
Decrease in restricted cash				$ 18,000,000
Collateral trust as a percent of value of bonds											50.00%