Investment in Kronos Worldwide, Inc. - Selected Financial Information of Kronos Balance Sheet (Detail) (Kronos, USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Kronos
Schedule Of Equity Method Investments [Line Items]
Current assets	$ 897.6	$ 781.2
Property and equipment, net	500.8	536.3
Investment in TiO2 joint venture	89.1	102.3
Other noncurrent assets	163.9	199.3
Total assets	1,651.4	1,619.1
Current liabilities	211.3	278.0
Long-term debt	345.7	180.4
Accrued pension and postretirement benefits	152.0	171.6
Other noncurrent liabilities	41.5	54.0
Stockholders' equity	900.9	935.1
Total liabilities and stockholders' equity	$ 1,651.4	$ 1,619.1