Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Stock-Based Compensation - Assumptions Used for Restricted Stock Grants (Details)

v3.23.1
Stock-Based Compensation - Assumptions Used for Restricted Stock Grants (Details) - Restricted Stock Units (Market Condition) - $ / shares
 12 Months Ended
Mar. 31, 2023
Mar. 31, 2022
August 2022 Grant    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield (per annum) 1.50%  
Expected volatility 41.90%  
Risk free interest rate 3.50%  
Expected life in years 3 years  
JHX stock price at grant date (A$ per share) $ 33.51  
Number of restricted stock units (in shares) 387,360  
August 2022 Grant    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield (per annum) 1.50%  
Expected volatility 33.40%  
Risk free interest rate 3.50%  
Expected life in years 2 years  
JHX stock price at grant date (A$ per share) $ 33.51  
Number of restricted stock units (in shares) 102,250  
November 2022 Grant    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield (per annum) 0.00%  
Expected volatility 42.50%  
Risk free interest rate 4.70%  
Expected life in years 9 months 18 days  
JHX stock price at grant date (A$ per share) $ 33.05  
Number of restricted stock units (in shares) 38,387  
November 2022 Grant    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield (per annum) 0.00%  
Expected volatility 35.10%  
Risk free interest rate 4.70%  
Expected life in years 1 year 9 months 18 days  
JHX stock price at grant date (A$ per share) $ 33.05  
Number of restricted stock units (in shares) 39,450  
November 2022 Grant    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield (per annum) 0.00%  
Expected volatility 43.80%  
Risk free interest rate 4.70%  
Expected life in years 2 years 9 months 18 days  
JHX stock price at grant date (A$ per share) $ 33.05  
Number of restricted stock units (in shares) 115,688  
March 2023 Grant    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield (per annum) 0.00%  
Expected volatility 36.30%  
Risk free interest rate 4.00%  
Expected life in years 2 years 4 months 24 days  
JHX stock price at grant date (A$ per share) $ 30.98  
Number of restricted stock units (in shares) 41,401  
August 2021 Grant    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield (per annum)   2.00%
Expected volatility   40.00%
Risk free interest rate   0.40%
Expected life in years   3 years
JHX stock price at grant date (A$ per share)   $ 52.66
Number of restricted stock units (in shares)   130,513
September 2021 Grant    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield (per annum)   2.00%
Expected volatility   40.20%
Risk free interest rate   0.40%
Expected life in years   2 years 10 months 24 days
JHX stock price at grant date (A$ per share)   $ 52.12
Number of restricted stock units (in shares)   92,956