v3.26.1
Organization and Significant Accounting Policies - Narrative (Details) - shares
3 Months Ended
Jul. 01, 2025
Jun. 30, 2026
Jun. 30, 2025
Summary Of Significant Accounting Policies [Line Items]      
Potential diluted common shares outstanding (in shares)   200,000 0
AZEK      
Summary Of Significant Accounting Policies [Line Items]      
James Hardie Common Shares issued (in shares) 148,861,787    
Contingent Shares Not Expected To Vest      
Summary Of Significant Accounting Policies [Line Items]      
Potential diluted common shares outstanding (in shares)   1,600,000 800,000