XML 86 R49.htm IDEA: XBRL DOCUMENT
v3.19.1

Summary of Significant Accounting Policies - ASU 2016-18 Adjustments (Details) $ in Millions, $ in Millions | 12 Months Ended | 60 Months Ended
--- | --- | ---
Mar. 31, 2019 USD ($) | Mar. 31, 2018 USD ($) | Mar. 31, 2017 USD ($) | Mar. 31, 2019 USD ($) | Mar. 31, 2019 AUD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cash and cash equivalents, restricted cash and restricted cash - Asbestos at beginning of period | $ 313.2 | $ 192.8 | $ 129.1 |  |
Cash and cash equivalents, restricted cash and restricted cash - Asbestos at end of period | 123.6 | 313.2 | 192.8 | $ 123.6 |
Cash paid to AICF | (103.0) | (102.2) | (91.1) | (472.1) | $ (595.3)
Asbestos liability | 1,089.6 | 1,215.1 |  | $ 1,089.6 |
Asbestos claims paid | (108.8) | (104.4) | (91.8) |  |
Net cash provided by operating activities | 287.6 | 302.0 | 382.5 |  |
Purchase of investments - Asbestos | (89.1) | (78.4) | 0.0 |  |
Proceeds from investments - Asbestos | 106.3 | 40.0 | 0.0 |  |
Net cash used in investing activities | (848.0) | (239.0) | (109.0) |  |
Proceeds from NSW Loan - Asbestos | 0.0 | 0.0 | 77.0 |  |
Repayments of NSW Loan - Asbestos | 0.0 | (51.9) | (74.3) |  |
Net cash used in financing activities | 364.2 | 60.6 | (210.0) |  |
Effects of exchange rate changes on cash | 6.6 | (3.2) | 0.2 |  |
As reported |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cash and cash equivalents, restricted cash and restricted cash - Asbestos at beginning of period | 281.6 | 78.9 | 107.1 |  |
Cash and cash equivalents, restricted cash and restricted cash - Asbestos at end of period |  | 281.6 | 78.9 |  |
Restricted cash - Asbestos |  | 95.2 | 0.9 |  |
Cash paid to AICF |  | (102.2) | (91.1) |  |
Asbestos liability |  | (104.4) | (92.0) |  |
Asbestos claims paid |  | 0.0 | 0.0 |  |
Net cash provided by operating activities |  | 295.0 | 292.1 |  |
Purchase of investments - Asbestos |  | 0.0 |  |  |
Proceeds from investments - Asbestos |  | 0.0 |  |  |
Net cash used in investing activities |  | (200.6) |  |  |
Proceeds from NSW Loan - Asbestos |  |  | 0.0 |  |
Repayments of NSW Loan - Asbestos |  | 0.0 | 0.0 |  |
Net cash used in financing activities |  | 112.5 | (212.7) |  |
Effects of exchange rate changes on cash |  | (4.2) | 1.4 |  |
ASU 2016-18 |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cash and cash equivalents, restricted cash and restricted cash - Asbestos at beginning of period | 313.2 | 192.8 | 129.1 |  |
Cash and cash equivalents, restricted cash and restricted cash - Asbestos at end of period |  | 313.2 | 192.8 |  |
Restricted cash - Asbestos |  | 0.0 | 0.0 |  |
Cash paid to AICF |  | 0.0 | 0.0 |  |
Asbestos liability |  | 0.0 | 0.0 |  |
Asbestos claims paid |  | (104.4) | (91.8) |  |
Net cash provided by operating activities |  | 302.0 | 382.5 |  |
Purchase of investments - Asbestos |  | (78.4) |  |  |
Proceeds from investments - Asbestos |  | 40.0 |  |  |
Net cash used in investing activities |  | (239.0) |  |  |
Proceeds from NSW Loan - Asbestos |  |  | 77.0 |  |
Repayments of NSW Loan - Asbestos |  | (51.9) | (74.3) |  |
Net cash used in financing activities |  | 60.6 | (210.0) |  |
Effects of exchange rate changes on cash |  | (3.2) | 0.2 |  |
ASU 2016-18 | Adjustment |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cash and cash equivalents, restricted cash and restricted cash - Asbestos at beginning of period | $ 31.6 | 113.9 | 22.0 |  |
Cash and cash equivalents, restricted cash and restricted cash - Asbestos at end of period |  | 31.6 | 113.9 |  |
Restricted cash - Asbestos |  | (95.2) | (0.9) |  |
Cash paid to AICF |  | 102.2 | 91.1 |  |
Asbestos liability |  | 104.4 | 92.0 |  |
Asbestos claims paid |  | (104.4) | (91.8) |  |
Net cash provided by operating activities |  | 7.0 | 90.4 |  |
Purchase of investments - Asbestos |  | (78.4) |  |  |
Proceeds from investments - Asbestos |  | 40.0 |  |  |
Net cash used in investing activities |  | (38.4) |  |  |
Proceeds from NSW Loan - Asbestos |  |  | 77.0 |  |
Repayments of NSW Loan - Asbestos |  | (51.9) | (74.3) |  |
Net cash used in financing activities |  | (51.9) | 2.7 |  |
Effects of exchange rate changes on cash |  | $ 1.0 | $ (1.2) |  |

X
- Definition Carrying amount as of the balance sheet date for total reserves related to asbestos claims. + References No definition available. + Details
Name: | jhx_AsbestosFundLiability
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Asbestos Net Claim Paid Adjustment including Handling Costs Incurred Paid + References No definition available. + Details
Name: | jhx_AsbestosNetClaimPaidAdjustmentincludingHandlingCostsIncurredPaid
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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
Name: | jhx_PaymentToFund
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Proceeds From Issuance Of Government Loans + References No definition available. + Details
Name: | jhx_ProceedsFromIssuanceOfGovernmentLoans
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Proceeds from restricted short-term investments Asbestos + References No definition available. + Details
Name: | jhx_ProceedsfromrestrictedshortterminvestmentsAsbestos
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Purchase of restricted short-term investments Asbestos + References No definition available. + Details
Name: | jhx_PurchaseofrestrictedshortterminvestmentsAsbestos
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Repayments Of Government Loans + References No definition available. + Details
Name: | jhx_RepaymentsOfGovernmentLoans
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Restricted Cash - Asbestos + References No definition available. + Details
Name: | jhx_RestrictedCashAsbestos
Namespace Prefix: | jhx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3044-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586 + Details
Name: | us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 230 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=98513438&loc=d3e33268-110906 + Details
Name: | us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 + Details
Name: | us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 + Details
Name: | us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
Name: | us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_RestatementAxis=srt_ScenarioPreviouslyReportedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201618Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RestatementAxis=srt_RestatementAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |