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Asbestos - Additional Information (Detail) |  |  | 12 Months Ended |  |  |  |  |  |
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Jul. 01, 2015 USD ($) | Jul. 01, 2015 AUD | Jul. 01, 2014 USD ($) | Jul. 01, 2014 AUD | Mar. 31, 2016 USD ($) | Mar. 31, 2016 AUD | Mar. 31, 2015 USD ($) | Mar. 31, 2013 USD ($) | Mar. 31, 2013 AUD | Jul. 02, 2012 USD ($) | Jul. 02, 2012 AUD | Apr. 02, 2012 USD ($) | Apr. 02, 2012 AUD | Mar. 31, 2012 USD ($)
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discounted (but inflated) central estimate lower range value |  |  |  |  | $ 1,000,000,000 | AUD 1,400,000,000 |  |  |  |  |  |  |  |
Discounted (but inflated) central estimate high range value |  |  |  |  | 2,600,000,000 | 3,400,000,000 |  |  |  |  |  |  |  |
Undiscounted (but inflated) central estimate lower range value |  |  |  |  | 1,300,000,000 | 1,700,000,000 |  |  |  |  |  |  |  |
Undiscounted (but inflated) central estimate high range value |  |  |  |  | 3,600,000,000 | 4,700,000,000 |  |  |  |  |  |  |  |
Potential increase in discounted central estimate |  |  |  |  |  |  | 30.00% |  |  |  |  |  |  |
Contribution to AICF |  |  |  |  |  |  |  | $ 184,100,000 | AUD 177,500,000 | $ 45,400,000 | AUD 45,200,000 | $ 138,700,000 | AUD 132,300,000 | $ 0
Secured standby loan facility maximum borrowing capacity |  |  |  |  | $ 245,000,000 | AUD 320,000,000 |  |  |  |  |  |  |  |
Secured standby loan Facility maturity date |  |  |  |  | Nov. 01, 2030 |  |  |  |  |  |  |  |  |
Loan facility, outstanding balance |  |  |  |  | $ 50,700,000 |  | $ 13,600,000 |  |  |  |  |  |  |
Rate of interest of Benchmark Bonds |  |  |  |  | 6.00% |  |  |  |  |  |  |  |  |
Maturity date of Benchmark Bonds |  |  |  |  | May 01, 2020 |  |  |  |  |  |  |  |  |
AICF Funding [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument Periodic payment | $ 62,800,000 | AUD 81,100,000 | $ 113,000,000 | AUD 119,900,000 |  |  |  |  |  |  |  |  |  |
Net cash provided by operating activities | $ 179,500,000 |  | $ 322,800,000 |  |  |  |  |  |  |  |  |  |  |
Maximum percentage of Free Cash Flow contributed to AICF | 35.00% | 35.00% | 35.00% | 35.00% |  |  |  |  |  |  |  |  |  |

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- Definition Total portion of carrying amounts as of the balance sheet date of AICF drawdown of loan facility with The State of New South Wales Australia. + References No definition available. + Details
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- Definition Maximum percentage of Free Cash Flow (as defined in the Amended and Restated Final Funding Agreement) in any given Financial year that is contributed to the Asbestos Injuries Compensation Fund in the next Financial Year. + References No definition available. + Details
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