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)

v3.22.1
Stock-Based Compensation - Assumptions Used for Restricted Stock Grants (Details) - Restricted Stock Units (Market Condition)
12 Months Ended
Mar. 31, 2022
$ / shares
shares
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) | $ / shares $ 52.66
Number of restricted stock units (in shares) | 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) | $ / shares $ 52.12
Number of restricted stock units (in shares) | shares 92,956
September 2020 Grant  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Dividend yield (per annum) 0.00%
Expected volatility 39.20%
Risk free interest rate 0.20%
Expected life in years 2 years 10 months 24 days
JHX stock price at grant date (A$ per share) | $ / shares $ 30.33
Number of restricted stock units (in shares) | shares 167,491
November 2020 Grant  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Dividend yield (per annum) 1.30%
Expected volatility 40.10%
Risk free interest rate 0.20%
Expected life in years 2 years 9 months 18 days
JHX stock price at grant date (A$ per share) | $ / shares $ 37.24
Number of restricted stock units (in shares) | shares 127,083