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Long-Term Debt - Additional Information (Detail) € in Millions |  |  | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Oct. 03, 2018 USD ($) | Oct. 03, 2018 EUR (€) | Oct. 01, 2018 | Dec. 31, 2017 USD ($) | Mar. 31, 2020 USD ($) instrument | Mar. 31, 2019 USD ($) | Mar. 31, 2018 USD ($) | Jul. 31, 2016 | Dec. 31, 2015 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Number of debt instruments held | instrument |  |  |  |  | 2 |  |  |  |
Repayments of Short-term Debt |  |  |  |  | $ 0 | $ 458,800,000 | $ 0 |  |
Loss on early debt extinguishment |  |  |  |  | 0 | 1,000,000.0 | 26,100,000 |  |
Letters of Credit Outstanding, Amount |  |  |  |  | 4,600,000 |  |  |  |
Senior Unsecured Notes Due First October Two Zero Two Six [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Unamortized balance of debt issuance costs |  |  |  |  | 5,000,000.0 | $ 5,700,000 |  |  |
Proceeds from long-term borrowings | $ 458,800,000 | € 400.0 |  |  | $ 440,700,000 |  |  |  |
Interest rate (as percent) |  |  |  |  | 3.625% | 3.625% |  |  |
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 |  |  |  |
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 |  |  |  |  | $ 395,700,000 |  |  |  |
Senior Unsecured Notes Due 15 February 2023 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Interest rate (as percent) |  |  |  |  |  |  |  | 5.875% |
Loss on early debt extinguishment |  |  |  |  |  |  | (26,100,000) |  |
Repayment of senior unsecured notes |  |  |  | $ 400,000,000.0 |  |  |  |  |
Redemption premium |  |  |  |  |  |  | 19,500,000 |  |
Unamortized financing costs |  |  |  |  |  |  | $ 6,600,000 |  |
Aggregate Principal Amount of Senior Unsecured Notes [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from long-term borrowings |  |  |  | 800,000,000.0 |  |  |  |  |
Aggregate Principal Amount of Senior Unsecured Notes [Member] | Level 1 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Estimated fair value of senior unsecured notes |  |  |  |  | 752,000,000.0 |  |  |  |
Senior Unsecured Notes Due 15 January 2025 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Unamortized balance of debt issuance costs |  |  |  |  | $ 4,300,000 | $ 5,200,000 |  |  |
Proceeds from long-term borrowings |  |  |  | $ 400,000,000.0 |  |  |  |  |
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 |  |  |  |
Senior Unsecured Notes Due15 January 2028 [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Unamortized balance of debt issuance costs |  |  |  |  | $ 4,900,000 | $ 5,600,000 |  |  |
Proceeds from long-term borrowings |  |  |  | $ 400,000,000.0 |  |  |  |  |
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 |  |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Weighted average interest rate on total outstanding debt (as percent) |  |  |  |  | 2.60% | 4.30% |  |  |
Maximum borrowing capacity |  |  |  |  |  |  |  |  | $ 500,000,000.0
Unsecured revolving credit facility, amount of increase |  |  |  |  |  |  |  |  | $ 250,000,000.0
Amortization period |  |  |  |  | 5 years |  |  |  |
Unamortized balance of debt issuance costs |  |  |  |  | $ 1,900,000 | $ 2,600,000 |  |  |
Amount drawn under line of credit |  |  |  |  | $ 130,000,000.0 | 150,000,000.0 |  |  |
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, |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity |  |  |  |  | $ 365,400,000 |  |  |  |
Revolving Credit Facility [Member] | Treasury Rate [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Percent of Excess Amount of Basis Spread |  |  |  |  |  |  | 0.50% |  |
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 |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Commitment fee percentage (as percent) |  |  |  |  | 0.20% |  |  |  |
Revolving Credit Facility [Member] | Minimum | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Credit facility interest rate applicable margins (as percent) |  |  |  |  | 1.25% |  |  |  |
Revolving Credit Facility [Member] | Minimum | Base Rate [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Credit facility interest rate applicable margins (as percent) |  |  |  |  | 0.25% |  |  |  |
Revolving Credit Facility [Member] | Maximum |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Commitment fee percentage (as percent) |  |  |  |  | 0.35% |  |  |  |
Revolving Credit Facility [Member] | Maximum | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Credit facility interest rate applicable margins (as percent) |  |  |  |  | 2.00% |  |  |  |
Revolving Credit Facility [Member] | Maximum | Base Rate [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Credit facility interest rate applicable margins (as percent) |  |  |  |  | 1.00% |  |  |  |
364-Day Term Loan Facility [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Repayments of Short-term Debt | € |  | € 400.0 |  |  |  |  |  |  |
Loss on early debt extinguishment |  |  |  |  |  | $ (1,000,000.0) |  |  |
Revolving Credit Facility and Senior Unsecured Notes [Member] |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |
Weighted average interest rate on total outstanding debt (as percent) |  |  |  |  | 4.30% | 4.40% |  |  |
Weighted average term of debt |  |  |  |  | 5 years 3 months 18 days | 6 years 3 months 18 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 Contractual interest rate for funds borrowed, under the debt agreement. + 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment. + 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(a)(3)) -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 (c) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=114001942&loc=d3e12355-112629 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114001942&loc=d3e12317-112629 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + 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 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + 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 The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share. + References No definition available. + Details
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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. + 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 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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