Business Segment Information - Holding Percentage of Subsidiaries (Detail)	Jun. 30, 2014
Kronos Worldwide, Inc.
Segment Reporting Information [Line Items]
Controlling interest in subsidiary	80.00%
CompX
Segment Reporting Information [Line Items]
Controlling interest in subsidiary	87.00%
WCS
Segment Reporting Information [Line Items]
Controlling interest in subsidiary	100.00%
BMI
Segment Reporting Information [Line Items]
Controlling interest in subsidiary	63.00%
LandWell | Aggregate General And Limited Interests
Segment Reporting Information [Line Items]
Controlling interest in subsidiary	77.00%