Business Segment Information - Additional Information (Detail)	Sep. 30, 2014
Kronos Worldwide, Inc.
Segment Reporting Information [Line Items]
Direct controlling interest in subsidiary	50.00%
Indirect controlling interest in subsidiary	30.00%
LandWell
Segment Reporting Information [Line Items]
Direct controlling interest in subsidiary	27.00%
Indirect controlling interest in subsidiary	50.00%
NL
Segment Reporting Information [Line Items]
Total controlling interest	83.00%