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Stock-Based Compensation - Assumptions Used for Restricted Stock Grants (Detail) (Restricted stock units (market condition) [Member], AUD)
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12 Months Ended | |
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Mar. 31, 2013
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Mar. 31, 2012
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Restricted stock units (market condition) [Member]
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Date of grant | Sep. 14, 2012 | Sep. 15, 2011 |
| Dividend yield (per annum) | 1.50% | 2.00% |
| Expected volatility | 52.20% | 51.90% |
| Risk free interest rate | 0.70% | 1.00% |
| Expected life in years | 3 years | 3 years |
| JHX stock price at grant date (A$) | 8.95 | 5.64 |
| Number of restricted stock units | 432,654 | 954,705 |
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- Definition
Share based compensation arrangement by share based payment award fair value assumptions date of grant. No definition available.
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- Definition
Share based compensation arrangement by share based payment award fair value assumptions grant date stock price. No definition available.
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- Definition
Share based compensation arrangement by share based payment award restricted stock units number. No definition available.
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- Definition
The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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