Noncontrolling Interest in Subsidiaries - Noncontrolling Interest in Subsidiaries (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Noncontrolling interest in net assets:
Noncontrolling interest in subsidiaries	$ 370.2	$ 391.5
Basic Management Inc.
Noncontrolling interest in net assets:
Noncontrolling interest in subsidiaries	31.5	33.7
LandWell
Noncontrolling interest in net assets:
Noncontrolling interest in subsidiaries	25.1	27.8
Kronos Worldwide, Inc.
Noncontrolling interest in net assets:
Noncontrolling interest in subsidiaries	239.0	241.9
NL
Noncontrolling interest in net assets:
Noncontrolling interest in subsidiaries	60.8	74.5
CompX
Noncontrolling interest in net assets:
Noncontrolling interest in subsidiaries	$ 13.8	$ 13.6