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v3.21.1

Asbestos - Summary of Net Unfunded AFFA Liability, Net of Tax (Details) $ in Millions, $ in Millions | 12 Months Ended
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Mar. 31, 2021 USD ($) | Mar. 31, 2021 AUD ($) | Mar. 31, 2020 USD ($) | Mar. 31, 2020 AUD ($) | Mar. 31, 2019 USD ($) | Mar. 31, 2019 AUD ($)
Asbestos Net Liability [Roll Forward] |  |  |  |  |  |
Change in claims handling cost estimate | $ (1.5) |  | $ 0.1 |  | $ 1.1 |
Net Unfunded AFFA Liability, net of tax |  |  |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |  |  |
Net Unfunded AFFA liability, net of tax, Beginning Balance | (544.4) |  |  |  |  |
Asbestos claims paid | 0.0 |  |  |  |  |
Payment received in accordance with AFFA | 153.3 |  |  |  |  |
AICF claims-handling costs incurred (paid) | 0.0 |  |  |  |  |
AICF operating costs paid - non claims-handling | (1.2) |  |  |  |  |
Change in actuarial estimate | (31.0) |  |  |  |  |
Change in claims handling cost estimate | (1.5) |  |  |  |  |
Impact on deferred income tax due to change in actuarial estimate | 9.7 |  |  |  |  |
Insurance recoveries | 0.0 |  |  |  |  |
Movement in income tax payable | (26.1) |  |  |  |  |
Other movements | 10.1 |  |  |  |  |
Effect of foreign exchange | (123.0) |  |  |  |  |
Net Unfunded AFFA liability, net of tax, Ending Balance | (554.1) |  | (544.4) |  |  |
Deferred Tax Assets |  |  |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |  |  |
Asbestos, deferred tax assets, beginning balance | 367.4 |  | 319.1 |  |  |
Impact on deferred income tax due to change in actuarial estimate | 9.7 |  |  |  |  |
Movement in income tax payable | (33.5) |  |  |  |  |
Other movements | 0.2 |  |  |  |  |
Effect of foreign exchange | 71.9 |  |  |  |  |
Asbestos, deferred tax assets, beginning balance | 367.4 |  | 319.1 |  |  |
Income Tax Payable |  |  |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |  |  |
Asbestos, income tax payable, beginning balance | 23.4 |  |  |  |  |
Movement in income tax payable | 7.4 |  |  |  |  |
Effect of foreign exchange | 4.4 |  |  |  |  |
Asbestos, income tax payable, ending balance | 35.2 |  | 23.4 |  |  |
Net Unfunded AFFA Liability |  |  |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |  |  |
Asbestos, net liability, beginning balance | (886.9) |  |  |  |  |
Payment received in accordance with AFFA | 153.3 |  |  |  |  |
AICF operating costs paid - non claims-handling | (1.2) |  |  |  |  |
Change in actuarial estimate | (31.0) |  |  |  |  |
Change in claims handling cost estimate | (1.5) |  |  |  |  |
Other movements | 9.9 |  |  |  |  |
Effect of foreign exchange | (199.3) |  |  |  |  |
Asbestos net liability, ending balance | (956.7) |  | (886.9) |  |  |
Asbestos Liability |  |  |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |  |  |
Asbestos, net liability, beginning balance | (986.4) |  |  |  |  |
Asbestos claims paid | 105.3 | $ 146.5 |  |  |  |
AICF claims-handling costs incurred (paid) | 1.1 |  |  |  |  |
Change in actuarial estimate | (33.0) |  |  |  |  |
Change in claims handling cost estimate | (1.5) |  |  |  |  |
Effect of foreign exchange | (221.3) |  |  |  |  |
Asbestos net liability, ending balance | (1,135.8) |  | (986.4) |  |  |
Insurance Receivables |  |  |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |  |  |
Asbestos, net liability, beginning balance | 43.5 |  |  |  |  |
Change in actuarial estimate | 2.0 |  |  |  |  |
Insurance recoveries | (5.8) |  |  |  |  |
Effect of foreign exchange | 9.8 |  |  |  |  |
Asbestos net liability, ending balance | 49.5 |  | 43.5 |  |  |
Restricted Cash and Investments |  |  |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |  |  |
Asbestos, net liability, beginning balance | 58.0 |  |  |  |  |
Asbestos claims paid | (105.3) |  |  |  |  |
Payment received in accordance with AFFA | 153.3 | $ 220.9 | 108.9 | $ 156.7 | $ 103.0 | $ 138.4
AICF claims-handling costs incurred (paid) | (1.1) |  |  |  |  |
AICF operating costs paid - non claims-handling | (1.2) |  |  |  |  |
Insurance recoveries | 5.8 |  |  |  |  |
Other movements | 9.5 |  |  |  |  |
Effect of foreign exchange | 12.5 |  |  |  |  |
Asbestos net liability, ending balance | 131.5 |  | 58.0 |  |  |
Other Assets and Liabilities |  |  |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |  |  |
Asbestos, net liability, beginning balance | (2.0) |  |  |  |  |
Other movements | 0.4 |  |  |  |  |
Effect of foreign exchange | (0.3) |  |  |  |  |
Asbestos net liability, ending balance | $ (1.9) |  | $ (2.0) |  |  |

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