XML 118 R103.htm IDEA: XBRL DOCUMENT v3.20.4
Noncontrolling Interest in Subsidiaries - Noncontrolling Interest in Net Assets of Subsidiaries (Detail) - USD ($)
$ in Millions
Dec. 31, 2020
Dec. 31, 2019
Noncontrolling interest in net assets:    
Noncontrolling interest in subsidiaries $ 324.4 $ 340.1
Kronos Worldwide, Inc.    
Noncontrolling interest in net assets:    
Noncontrolling interest in subsidiaries 212.3 216.6
NL Industries    
Noncontrolling interest in net assets:    
Noncontrolling interest in subsidiaries 67.1 65.8
CompX International    
Noncontrolling interest in net assets:    
Noncontrolling interest in subsidiaries 23.5 22.7
BMI    
Noncontrolling interest in net assets:    
Noncontrolling interest in subsidiaries 14.7 20.1
LandWell    
Noncontrolling interest in net assets:    
Noncontrolling interest in subsidiaries $ 6.8 $ 14.9