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Asbestos - Narrative (Details) $ in Millions, $ in Millions | 12 Months Ended | 51 Months Ended |
--- | --- | --- | ---
Mar. 31, 2023 USD ($) | Mar. 31, 2023 AUD ($) | Mar. 31, 2022 USD ($) | Mar. 31, 2022 AUD ($) | Mar. 31, 2021 USD ($) | Mar. 31, 2021 AUD ($) | Mar. 31, 2020 USD ($) | Mar. 31, 2020 AUD ($) | Mar. 31, 2022 USD ($) | Mar. 31, 2022 AUD ($) | Mar. 31, 2022 AUD ($)
Schedule Of Asbestos Claims [Line Items] |  |  |  |  |  |  |  |  |  |  |
Percent of claims above actuarial expectations |  |  | 1.00% | 1.00% |  |  |  |  |  |  |
Percent of claims compared to prior corresponding period |  |  | 3.00% | 3.00% |  |  |  |  |  |  |
Percent of net cash outflows below actuarial expectations |  |  | 1.00% | 1.00% |  |  |  |  |  |  |
Cash paid to AICF |  |  | $ 248.5 |  | $ 153.3 |  | $ 108.9 |  | $ 715.9 | $ 979.1 |
Secured standby loan facility maximum borrowing capacity |  |  | 239.4 |  |  |  |  |  | $ 239.4 |  | $ 320.0
Restricted Cash and Investments |  |  |  |  |  |  |  |  |  |  |
Schedule Of Asbestos Claims [Line Items] |  |  |  |  |  |  |  |  |  |  |
Payment received in accordance with AFFA |  |  | $ 248.5 | $ 328.2 | $ 153.3 | $ 220.9 | $ 108.9 | $ 156.7 |  |  |
Scenario, Forecast | AICF Funding |  |  |  |  |  |  |  |  |  |  |
Schedule Of Asbestos Claims [Line Items] |  |  |  |  |  |  |  |  |  |  |
Cash paid to AICF | $ 117.8 | $ 157.5 |  |  |  |  |  |  |  |  |
Central Estimate – Discounted and Inflated |  |  |  |  |  |  |  |  |  |  |
Schedule Of Asbestos Claims [Line Items] |  |  |  |  |  |  |  |  |  |  |
Discounted actuarial estimate, potential period shift |  |  | 2 years | 2 years |  |  |  |  |  |  |
Discounted actuarial estimate, potential percent increase |  |  | 21.00% |  |  |  |  |  | 21.00% |  | 21.00%

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- Definition Asbestos Claims, Net Cash Outflow, Percent Below Actuarial Expectations + References No definition available. + Details
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- Definition Asbestos Claims, Reporting Activity, Percent Above Actuarial Expectations + References No definition available. + Details
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- Definition Asbestos Claims, Reporting Activity, Percent Compared to Prior Period + References No definition available. + Details
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- Definition Under the terms of the Amended and Restated Final Funding Agreement (AFFA), a wholly owned Australian subsidiary (the Performing Subsidiary) has an obligation to make payments to the AICF on an annual basis. The amount of these annual payments is dependent on several factors, including the Company's free cash flow (as defined by the AFFA), actuarial estimations, actual claims paid, operating expenses of the AICF and the annual cash flow cap. + References No definition available. + Details
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