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Asbestos - Asbestos Adjustments (Details) - USD ($) $ in Millions | 12 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020 | Mar. 31, 2019
Change in estimates: |  |  |
Change in actuarial estimate - asbestos liability | $ (33.0) | $ (133.8) | $ (73.8)
Change in actuarial estimate - insurance receivable | 2.0 | 5.7 | 0.0
Change in estimate - AICF claims-handling costs | (1.5) | 0.1 | 1.1
Subtotal - Change in estimates | (32.5) | (128.0) | (72.7)
Effect of foreign exchange on Asbestos net liabilities | (123.0) | 69.0 | 49.5
Gain (loss) on foreign currency forward contracts | 11.7 | 0.8 | (0.8)
Adjustments in insurance receivable | 0.0 | 0.0 | 2.0
Other | (0.1) | 0.0 | 0.0
Total Asbestos Adjustments | $ (143.9) | $ (58.2) | $ (22.0)

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- Definition Adjustment in Insurance Receivable, Asbestos + References No definition available. + Details
Name: | jhx_AdjustmentinInsuranceReceivableAsbestos
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Balance Type: | debit
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- Definition Gain (loss) on foreign exchange movements in the other asbestos related assets and liabilities which are denominated in Australian dollars. + References No definition available. + Details
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- Definition Comprised of changes in actuarial estimates received as of March 31 each year and the effect of foreign exchange movements in the asbestos related assets and liabilities which are denominated in Australian dollars. + References No definition available. + Details
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- Definition Asbestos Adjustments, Other + References No definition available. + Details
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- Definition Change in actuarial estimate asbestos liability. + References No definition available. + Details
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- Definition Change in actuarial estimate insurance receivables. + References No definition available. + Details
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- Definition Change in estimate claims handling costs. + References No definition available. + Details
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- Definition Change in estimates. + References No definition available. + Details
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- Definition Changes in estimates. + References No definition available. + Details
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- Definition Gain (Loss) on Foreign Currency Forwards Contracts, Asbestos + References No definition available. + Details
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