Annual and transition report of foreign private issuers [Sections 13 or 15(d)]

Restructuring Expenses - Schedule of Restructuring and Related Costs (Details)

v3.25.1
Restructuring Expenses - Schedule of Restructuring and Related Costs (Details) - USD ($)
$ in Millions
 12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Restructuring Cost and Reserve [Line Items]    
Restructuring costs $ 50.3 $ 20.1
Segment Reporting, Reconciling Item, Corporate Nonsegment [Member]    
Restructuring Cost and Reserve [Line Items]    
Restructuring costs 0.0 20.1
Asia Pacific Fiber Cement    
Restructuring Cost and Reserve [Line Items]    
Restructuring costs 50.3 0.0
Equipment write-offs, including disposal costs | Asia Pacific Fiber Cement    
Restructuring Cost and Reserve [Line Items]    
Restructuring costs 30.3 0.0
Reclassification of foreign currency translation adjustments | Asia Pacific Fiber Cement    
Restructuring Cost and Reserve [Line Items]    
Restructuring costs 8.3 0.0
Other exit costs | Asia Pacific Fiber Cement    
Restructuring Cost and Reserve [Line Items]    
Restructuring costs $ 11.7 $ 0.0