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

Segment and Geographic Information - Capital Expenditures (Details)

v3.25.1
Segment and Geographic Information - Capital Expenditures (Details) - USD ($)
$ in Millions
 12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Mar. 31, 2023
Segment Reporting Information [Line Items]      
Capital expenditures incurred but not yet paid $ 422.2 $ 449.3 $ 591.3
Operating Segments | North America Fiber Cement      
Segment Reporting Information [Line Items]      
Capital expenditures incurred but not yet paid 287.2 298.1 392.0
Operating Segments | Asia Pacific Fiber Cement      
Segment Reporting Information [Line Items]      
Capital expenditures incurred but not yet paid 53.1 47.8 136.2
Operating Segments | Europe Building Products      
Segment Reporting Information [Line Items]      
Capital expenditures incurred but not yet paid 74.3 89.7 57.8
General Corporate and R&D      
Segment Reporting Information [Line Items]      
Capital expenditures incurred but not yet paid $ 7.6 $ 13.7 $ 5.3