XML 114 R77.htm IDEA: XBRL DOCUMENT
v3.20.1

Asbestos - Summary of Net Unfunded AFFA Liability, Net of Tax (Detail) $ in Millions, $ in Millions | 12 Months Ended
--- | ---
Mar. 31, 2020 USD ($) | Mar. 31, 2020 AUD ($) | Mar. 31, 2019 USD ($) | Mar. 31, 2018 USD ($)
Asbestos Net Liability [Roll Forward] |  |  |  |
Asbestos Net Liability | $ (886.9) |  | $ (983.0) |
Deferred income taxes - Asbestos | 319.1 |  | 349.3 |
Income Tax Payable Asbestos | 23.4 |  | 25.3 |
Net Unfunded AFFA liability, net of tax, Beginning Balance | (608.4) |  |  |
AICF operating costs paid - non claims-handling | 1.7 |  | (1.5) | $ (1.9)
Change in claims handling cost estimate | 0.1 |  | 1.1 | $ (0.5)
Net Unfunded AFFA liability, net of tax, Ending Balance | (544.4) |  | (608.4) |
Asbestos Liability |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |
Asbestos Net Liability | (986.4) |  | (1,089.6) |
Asbestos claims paid | 104.6 | $ 153.3 |  |
AICF claims-handling costs incurred (paid) | 1.0 |  |  |
Change in actuarial estimate | (133.8) |  |  |
Change in claims handling cost estimate | (0.1) |  |  |
Effect of foreign exchange | (131.3) |  |  |
Insurance Receivables |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |
Asbestos Net Liability | 43.5 |  | 51.2 |
Change in actuarial estimate | 5.7 |  |  |
Insurance recoveries | 7.6 |  |  |
Effect of foreign exchange | 5.8 |  |  |
Restricted Cash and Investments |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |
Asbestos Net Liability | 58.0 |  | 57.5 |
Asbestos claims paid | (104.6) |  |  |
Payment received in accordance with AFFA | 108.9 |  |  |
AICF claims-handling costs incurred (paid) | (1.0) |  |  |
AICF operating costs paid - non claims-handling | 1.7 |  |  |
Insurance recoveries | (7.6) |  |  |
Other movements | 3.2 |  |  |
Effect of foreign exchange | 11.9 |  |  |
Other Assets and Liabilities |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |
Asbestos Net Liability | (2.0) |  | $ (2.1) |
Other movements | (1.1) |  |  |
Effect of foreign exchange | (1.2) |  |  |
Net Unfunded AFFA Liability |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |
Payment received in accordance with AFFA | 108.9 | $ 156.7 |  |
AICF operating costs paid - non claims-handling | (1.7) |  |  |
Change in actuarial estimate | (128.1) |  |  |
Change in claims handling cost estimate | 0.1 |  |  |
Insurance recoveries | 0.0 |  |  |
Other movements | 2.1 |  |  |
Effect of foreign exchange | 114.8 |  |  |
Deferred Tax Assets |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |
Impact on deferred income tax due to change in actuarial estimate | (38.4) |  |  |
Movement in income tax payable | 25.8 |  |  |
Other movements | 0.3 |  |  |
Effect of foreign exchange | 43.1 |  |  |
Income Tax Payable |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |
Movement in income tax payable | (0.8) |  |  |
Other movements | 0.0 |  |  |
Effect of foreign exchange | 2.7 |  |  |
Net Unfunded AFFA Liability, net of tax |  |  |  |
Asbestos Net Liability [Roll Forward] |  |  |  |
Asbestos claims paid | 0.0 |  |  |
Payment received in accordance with AFFA | 108.9 |  |  |
AICF claims-handling costs incurred (paid) | 0.0 |  |  |
AICF operating costs paid - non claims-handling | (1.7) |  |  |
Change in actuarial estimate | (128.1) |  |  |
Change in claims handling cost estimate | 0.1 |  |  |
Impact on deferred income tax due to change in actuarial estimate | 38.4 |  |  |
Insurance recoveries | 0.0 |  |  |
Movement in income tax payable | (25.0) |  |  |
Other movements | 2.4 |  |  |
Effect of foreign exchange | $ 69.0 |  |  |

X
- Definition AICF operating cost paid non claim handling. + References No definition available. + Details
Name: | jhx_AicfOperatingCostPaidNonClaimHandling
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Portion of deferred income tax asset that becomes available to the Company as an Australian tax deduction resulting from the Company's previous contributions to AICF. + References No definition available. + Details
Name: | jhx_AmountOfDeferredTaxAssetsAppliedToIncomeTaxPayable
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Asbestos change in actuarial estimate. + References No definition available. + Details
Name: | jhx_AsbestosChangeInActuarialEstimate
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Asbestos injuries compensation fund claims handling costs incurred or paid. + References No definition available. + Details
Name: | jhx_AsbestosInjuriesCompensationFundClaimsHandlingCostsIncurredPaid
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Other movements in the asbestos liability, either increasing or decreasing the liability. + References No definition available. + Details
Name: | jhx_AsbestosLiabilityOtherChanges
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Asbestos liability net claims paid. + References No definition available. + Details
Name: | jhx_AsbestosNetClaimPaidAdjustment
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Asbestos net liability in accordance with the Amended and Restated Final Funding Agreement. + References No definition available. + Details
Name: | jhx_AsbestosNetLiability
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Asbestos net liability in accordance with the Amended and Restated Final Funding Agreement, net of tax. + References No definition available. + Details
Name: | jhx_AsbestosNetLiabilityNetTax
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Asbestos Net Liability [Roll Forward] + References No definition available. + Details
Name: | jhx_AsbestosNetLiabilityRollForward
Namespace Prefix: | jhx_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Change in estimate claims handling costs. + References No definition available. + Details
Name: | jhx_ChangeInEstimateClaimsHandlingCosts
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Non current portion of Australian tax benefits as of the balance sheet date that will be available to the Company in relation to the Company's contributions to the AICF. + References No definition available. + Details
Name: | jhx_DeferredTaxAssetsNetAsbestosNoncurrent
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Foreign exchange gain or loss in the asbestos liability due to change in closing exchange rates between the currencies at the beginning and ending balance sheet dates. + References No definition available. + Details
Name: | jhx_ForeignExchangeGainLossInAsbestosLiability
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Impact on deferred income tax due to change in actuarial estimate. + References No definition available. + Details
Name: | jhx_ImpactOnDeferredIncomeTaxDueToChangeInActuarialEstimate
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Australian tax deduction available to be taken by the Company resulting from the Company's previous contributions to AICF. + References No definition available. + Details
Name: | jhx_IncomeTaxPayableAsbestos
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount recovered from insurance related to asbestos claims. + References No definition available. + Details
Name: | jhx_InsuranceRecoveriesAsbestosAdjustment
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Payments received in accordance with amended and restated final funding agreement. + References No definition available. + Details
Name: | jhx_PaymentsReceivedInAccordanceWithAmendedAndRestatedFinalFundingAgreement
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=jhx_AsbestosLiabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=jhx_InsuranceReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=jhx_RestrictedCashAndShortTermInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=jhx_OtherAssetsAndLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=jhx_NetUnfundedAFFALiabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=jhx_DeferredTaxAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=jhx_IncomeTaxPayableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=jhx_NetUnfundedAFFALiabilityNetofTaxMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |