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Long-Term Debt - Additional Information (Detail) € in Millions |  |  |  |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Oct. 03, 2018 USD ($) | Oct. 03, 2018 EUR (€) | Oct. 01, 2018 EUR (€) | Apr. 25, 2018 USD ($) | Apr. 03, 2018 USD ($) | Apr. 03, 2018 EUR (€) | Dec. 31, 2017 USD ($) | Jul. 31, 2016 USD ($) | Feb. 28, 2015 USD ($) | Mar. 31, 2019 USD ($) instrument | Mar. 31, 2019 EUR (€) | Mar. 31, 2018 USD ($) instrument | Mar. 31, 2017 USD ($) | Dec. 31, 2015 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of debt instruments held | instrument |  |  |  |  |  |  |  |  |  | 2 |  | 3 |  |
Proceeds from 364-day term loan facility |  |  |  |  |  |  |  |  |  | $ 492,400,000 |  | $ 0 | $ 0 |
Repayments of Short-term Debt |  |  |  |  |  |  |  |  |  | 458,800,000 |  | 0 | 0 |
Loss on early debt extinguishment |  |  |  |  |  |  |  |  |  | 1,000,000 |  | 26,100,000 | 0 |
Repayment of senior unsecured notes |  |  |  |  |  |  |  |  |  | 0 |  | 400,000,000 | $ 0 |
Letters of Credit Outstanding, Amount |  |  |  |  |  |  |  |  |  | 9,500,000 |  |  |  |
Senior Unsecured Notes Due First October Two Zero Two Six [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized balance of debt issuance costs |  |  |  |  |  |  |  |  |  | 5,700,000 |  |  |  |
Proceeds from long-term borrowings | $ 458,800,000 | € 400.0 | € 400.0 |  |  |  |  |  |  | $ 449,400,000 |  |  |  |
Interest rate (as percent) |  |  |  |  |  |  |  |  |  | 3.625% |  |  |  |
Loss on early debt extinguishment |  |  |  |  |  |  |  |  |  | $ (1,000,000) |  |  |  |
Debt issuance cost amortization period |  |  | 8 years |  |  |  |  |  |  |  |  |  |  |
Frequency of payments |  |  |  |  |  |  |  |  |  | Interest is payable semi-annually in arrears on 1 October and 1 April of each year | Interest is payable semi-annually in arrears on 1 October and 1 April of each year |  |  |
Senior Unsecured Notes Due First October Two Zero Two Six [Member] | Level 1 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated fair value of senior unsecured notes |  |  |  |  |  |  |  |  |  | $ 456,900,000 |  |  |  |
Senior Unsecured Notes Due 15 February 2023 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from long-term borrowings |  |  |  |  |  |  |  |  | $ 325,000,000 |  |  |  |  |
Interest rate (as percent) |  |  |  |  |  |  |  |  | 5.875% | 5.875% |  |  |  |
Loss on early debt extinguishment |  |  |  |  |  |  |  |  |  |  |  | 26,100,000 |  |
Aggregate principal amount after re-offering |  |  |  |  |  |  |  | $ 400,000,000 |  |  |  |  |  |
Redemption premium |  |  |  |  |  |  |  |  |  |  |  | 19,500,000 |  |
Unamortized financing costs |  |  |  |  |  |  |  |  |  |  |  | 6,600,000 |  |
Repayment of senior unsecured notes |  |  |  |  |  |  | $ 400,000,000 |  |  |  |  |  |  |
Senior Unsecured Notes Due 15 February 2023 Re-offering [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from long-term borrowings |  |  |  |  |  |  |  | $ 75,000,000 |  |  |  |  |  |
Interest rate (as percent) |  |  |  |  |  |  |  | 5.875% |  |  |  |  |  |
Aggregate Principal Amount of Senior Unsecured Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from long-term borrowings |  |  |  |  |  |  | 800,000,000 |  |  |  |  |  |  |
Aggregate Principal Amount of Senior Unsecured Notes [Member] | Global Exchange Market Listing [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from long-term borrowings |  |  |  | $ 800,000,000 |  |  |  |  |  |  | € 400.0 |  |  |
Aggregate Principal Amount of Senior Unsecured Notes [Member] | Level 1 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated fair value of senior unsecured notes |  |  |  |  |  |  |  |  |  | $ 774,000,000 |  |  |  |
Senior Unsecured Notes Due 15 January 2025 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized balance of debt issuance costs |  |  |  |  |  |  |  |  |  | $ 5,200,000 |  | 6,100,000 |  |
Proceeds from long-term borrowings |  |  |  |  |  |  | $ 400,000,000 |  |  |  |  |  |  |
Interest rate (as percent) |  |  |  |  |  |  |  |  |  | 4.75% |  |  |  |
Debt issuance cost amortization period |  |  |  |  |  |  | 7 years |  |  |  |  |  |  |
Frequency of payments |  |  |  |  |  |  |  |  |  | Interest is payable semi-annually in arrears on 15 January and 15 July of each year | Interest is payable semi-annually in arrears on 15 January and 15 July of each year |  |  |
Senior Unsecured Notes Due15 January 2028 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized balance of debt issuance costs |  |  |  |  |  |  |  |  |  | $ 5,600,000 |  | $ 6,200,000 |  |
Proceeds from long-term borrowings |  |  |  |  |  |  | $ 400,000,000 |  |  |  |  |  |  |
Interest rate (as percent) |  |  |  |  |  |  |  |  |  | 5.00% |  |  |  |
Debt issuance cost amortization period |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |
Frequency of payments |  |  |  |  |  |  |  |  |  | Interest is payable semi-annually in arrears on 15 January and 15 July of each year | Interest is payable semi-annually in arrears on 15 January and 15 July of each year |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on total outstanding debt (as percent) |  |  |  |  |  |  |  |  |  | 4.30% |  | 3.20% |  |
Maximum borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 500,000,000.0
Unsecured revolving credit facility, amount of increase |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 250,000,000.0
Amortization period |  |  |  |  |  |  |  |  |  | 5 years | 5 years |  |  |
Unamortized balance of debt issuance costs |  |  |  |  |  |  |  |  |  | $ 2,600,000 |  | $ 3,300,000 |  |
Amount drawn under line of credit |  |  |  |  |  |  |  |  |  | $ 150,000,000 |  | $ 100,000,000 |  |
Credit facility interest rate description |  |  |  |  |  |  |  |  |  |  |  | The base rate is calculated as the highest of (x) the rate that the administrative agent announces from time to time as its prime lending rate, as in effect from time to time, (y) 1/2 of 1% in excess of the overnight Federal Funds Rate, and (z) LIBOR for an interest period of one month plus 1.00%. |  |
Credit facility alternate applicable interest rate, commitment fee (as percent) |  |  |  |  |  |  |  |  |  | 0.25% |  |  |  |
Credit facility alternate applicable interest rate, LIBOR loans (as percent) |  |  |  |  |  |  |  |  |  | 1.50% |  |  |  |
Credit facility alternate applicable interest rate, base rate loans (as percent) |  |  |  |  |  |  |  |  |  | 0.50% |  |  |  |
Debt covenant description in credit facility agreement |  |  |  |  |  |  |  |  |  | The Revolving Credit Facility agreement contains certain covenants that, among other things, restrict JHIGL and its restricted subsidiaries’ ability to incur indebtedness and grant liens other than certain types of permitted indebtedness and permitted liens, make certain restricted payments, and undertake certain types of mergers or consolidations actions. In addition, the Company: (i) must not exceed a maximum ratio of net debt to earnings before interest, tax, depreciation and amortization, excluding all asbestos-related liabilities, assets, income, gains, losses and charges other than AICF payments, all AICF selling, general and administrative (“SG&A”) expenses, all Australian Securities and Investment Commission (“ASIC”)-related expenses, all recoveries and asset impairments, and all New Zealand product liability expenses and (ii) must meet or exceed a minimum ratio of earnings before interest, | The Revolving Credit Facility agreement contains certain covenants that, among other things, restrict JHIGL and its restricted subsidiaries’ ability to incur indebtedness and grant liens other than certain types of permitted indebtedness and permitted liens, make certain restricted payments, and undertake certain types of mergers or consolidations actions. In addition, the Company: (i) must not exceed a maximum ratio of net debt to earnings before interest, tax, depreciation and amortization, excluding all asbestos-related liabilities, assets, income, gains, losses and charges other than AICF payments, all AICF selling, general and administrative (“SG&A”) expenses, all Australian Securities and Investment Commission (“ASIC”)-related expenses, all recoveries and asset impairments, and all New Zealand product liability expenses and (ii) must meet or exceed a minimum ratio of earnings before interest, |  |  |
Line of Credit Facility, Remaining Borrowing Capacity |  |  |  |  |  |  |  |  |  | $ 340,500,000 |  |  |  |
Revolving Credit Facility [Member] | Treasury Rate [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Percent of Excess Amount of Basis Spread |  |  |  |  |  |  |  |  |  |  |  | 0.50% |  |
Debt Instrument, Excess of Basis Spread As Percent |  |  |  |  |  |  |  |  |  |  |  | 1.00% |  |
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility interest rate applicable margins (as percent) |  |  |  |  |  |  |  |  |  |  |  | 1.00% |  |
Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee percentage (as percent) |  |  |  |  |  |  |  |  |  | 0.20% | 0.20% |  |  |
Revolving Credit Facility [Member] | Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility interest rate applicable margins (as percent) |  |  |  |  |  |  |  |  |  | 1.25% | 1.25% |  |  |
Revolving Credit Facility [Member] | Minimum [Member] | Base Rate [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility interest rate applicable margins (as percent) |  |  |  |  |  |  |  |  |  | 0.25% | 0.25% |  |  |
Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee percentage (as percent) |  |  |  |  |  |  |  |  |  | 0.35% | 0.35% |  |  |
Revolving Credit Facility [Member] | Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility interest rate applicable margins (as percent) |  |  |  |  |  |  |  |  |  | 2.00% | 2.00% |  |  |
Revolving Credit Facility [Member] | Maximum [Member] | Base Rate [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility interest rate applicable margins (as percent) |  |  |  |  |  |  |  |  |  | 1.00% | 1.00% |  |  |
364-Day Term Loan Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, term |  |  |  |  |  |  |  |  |  |  |  | 364 days |  |
Proceeds from 364-day term loan facility |  |  |  |  | $ 492,400,000 | € 400.0 |  |  |  |  |  |  |  |
Repayments of Short-term Debt | € |  |  |  |  |  |  |  |  |  |  | € 400.0 |  |  |
Revolving Credit Facility and Senior Unsecured Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on total outstanding debt (as percent) |  |  |  |  |  |  |  |  |  | 4.40% |  | 4.70% |  |
Weighted average term of debt |  |  |  |  |  |  |  |  |  | 6 years 3 months 19 days | 6 years 3 months 19 days | 6 years 10 months 25 days |  |

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- Definition Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
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- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
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- Definition Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585 + Details
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