Consolidated funded indebtedness ratio.

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Debt instrument maturity period.

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Indebtedness ratio maintain date earliest

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Indebtedness ratio maintain date latest

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Interest coverage ratio minimum.

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Letter of credit maximum capacity.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Latest date when the debt instrument can be converted into equity, in CCYY-MM-DD format.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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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.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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No definition available.

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Date the credit facility terminates, in CCYY-MM-DD format.

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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).

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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.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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The carrying value as of the balance sheet date of the noncurrent portion 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.

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The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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Long-Term Debt - Additional Information (Detail) - USD ($)					9 Months Ended
	Dec. 20, 2019	Oct. 02, 2019	Aug. 02, 2016	Oct. 31, 2014	Dec. 31, 2019	Mar. 31, 2019
Debt Instrument [Line Items]
Bank Credit Facility, borrowings available					$ 158,100,000
Interest coverage ratio				250.00%
Borrowings outstanding under Credit Facility					585,000,000	$ 310,000,000
Letter of Credit Facility					40,000,000.0
Outstanding letters of credit , amount					6,900,000
Debt instrument, principal amount					935,000,000	696,500,000
Repayments of Debt					$ 36,500,000
Minimum [Member]
Debt Instrument [Line Items]
Unused line of credit commitment fee based on leverage ratio				0.15%
Maximum [Member]
Debt Instrument [Line Items]
Unused line of credit commitment fee based on leverage ratio				0.30%
December 31,2019 and June 30,2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Earliest Date				Dec. 31, 2019
Debt Instrument, Convertible, Latest Date				Jun. 30, 2020
December 31,2019 and June 30,2020 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Consolidated funded indebtedness ratio				400.00%
September 30,2020 and December 31,2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Earliest Date				Sep. 30, 2020
Debt Instrument, Convertible, Latest Date				Dec. 31, 2020
September 30,2020 and December 31,2020 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Consolidated funded indebtedness ratio				375.00%
After december 31,2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Earliest Date				Dec. 31, 2020
After december 31,2020 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Consolidated funded indebtedness ratio				350.00%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Variable margin				1.25%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Variable margin				2.00%
Federal Funds Effective Swap Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Variable margin				0.25%
Federal Funds Effective Swap Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Variable margin				1.00%
Term Loan Agreement [Member]
Debt Instrument [Line Items]
Credit Facility, interest rate description					Borrowings under the Term Loan Agreement will bear interest, at our option, at a floating rate per annum equal to either the alternate base rate (consistent with the Amended Credit Facility), plus a margin between 25 and 100 basis points, or based on the adjusted LIBOR plus a margin between 125 and 200 basis points, depending on the ratio of our consolidated indebtedness to consolidated EBITDA (consistent with the Amended Credit Facility). We must also maintain a ratio of consolidated indebtedness to consolidated EBITDA consistent with the Amended Credit Facility.
Term loan facility, unused borrowing capacity, Amount	$ 665,000,000.0
Term loan borrowing, Amount					$ 0
Term loan Maturity Date					Aug. 02, 2021
Term Loan Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Variable margin	0.25%
Term Loan Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Variable margin	1.00%
Term Loan Agreement [Member] \| Federal Funds Effective Swap Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Consolidated funded indebtedness ratio	1.25%
Term Loan Agreement [Member] \| Federal Funds Effective Swap Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Consolidated funded indebtedness ratio	2.00%
4.500% Senior Unsecured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount			$ 350,000,000.0		$ 350,000,000	350,000,000
Debt instrument, interest rate			4.50%		4.50%
Debt instrument, maturity period			2026-08
4.500% Senior Unsecured Notes Due 2026 [Member] \| Prior to August 1, 2021 [Member]
Debt Instrument [Line Items]
Redemption price, percentage			100.00%
Private Placement Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount						$ 36,500,000
Repayments of Debt		$ 36,500,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit Facility, principal balance					$ 500,000,000.0
Bank Credit Facility, borrowings available					$ 750,000,000.0
Credit Facility, termination date					Aug. 02, 2021
Credit Facility, interest rate description					At our option, outstanding principal amounts on the Amended Credit Facility bear interest at a variable rate equal to either (i) the LIBOR plus an agreed margin (ranging from 125 to 200 basis points), which is to be established quarterly based on the Company's ratio of consolidated EBITDA, defined as earnings before interest, taxes, depreciation, and amortization, to the Company's consolidated indebtedness (the Leverage Ratio); or (ii) an alternate base rate, which is the highest of (a) the prime rate, (b) the federal funds rate plus ½% per annum, or (c) one month LIBOR plus 1.0%, in each case plus an agreed margin (ranging from 25 to 100 basis points). In the case of loans bearing interest at a rate based on the alternate base rate, interest payments are payable quarterly. In the case of loans bearing interest at a rate based on LIBOR, interest is payable at the end of the LIBOR advance periods, which can be up to six months at the option of the Company. The Company is also required to pay a commitment fee on unused available borrowings under the Amended Credit Facility ranging from 15 to 30 basis points depending upon the Leverage Ratio.
Revolving Credit Facility [Member] \| Swingline Loan [Member]
Debt Instrument [Line Items]
Credit Facility, principal balance					$ 25,000,000.0
Line of Credit \| Federal Funds Effective Swap Rate [Member]
Debt Instrument [Line Items]
Variable margin				0.50%
Letter of Credit [Member]
Debt Instrument [Line Items]
Bank Credit Facility, one-time fee					0.125%