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Asbestos - Central Estimates, Net of Insurance Recoveries (Detail) - Mar. 31, 2020 $ in Millions, $ in Millions | USD ($) | AUD ($)
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Central Estimate – Discounted and Inflated |  |
Asbestos Claims [Line Items] |  |
Asbestos Liability Actuarial Estimate | $ 1,250.9 | $ 2,025.2
Range Of Discounted Actuarial Estimate Minimum | 913.0 | 1,478.2
Range Of Discounted Actuarial Estimate Maximum | 2,109.3 | 3,414.9
Central Estimate – Undiscounted but Inflated |  |
Asbestos Claims [Line Items] |  |
Asbestos Liability Actuarial Estimate | 1,368.3 | 2,215.2
Central Estimate – Undiscounted but Inflated | Minimum |  |
Asbestos Claims [Line Items] |  |
Range Of Un Discounted Actuarial Estimate Minimum | 984.3 | 1,593.6
Central Estimate – Undiscounted but Inflated | Maximum |  |
Asbestos Claims [Line Items] |  |
Range Of Un Discounted Actuarial Estimate Maximum | 2,385.2 | 3,861.7
Central Estimate – Undiscounted and Uninflated |  |
Asbestos Claims [Line Items] |  |
Asbestos Liability Actuarial Estimate | $ 897.1 | $ 1,452.4

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