Consolidated funded indebtedness ratio.

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Debt instrument maturity period.

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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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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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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Weighted average interest rate of debt outstanding.

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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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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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

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Percentage of tier one capital to total leverage exposure, as defined by regulatory framework.

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No definition available.

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Indebtedness - Additional Information (Detail) - USD ($)						12 Months Ended
	Apr. 09, 2020	Dec. 20, 2019	Oct. 02, 2019	Aug. 02, 2016	Oct. 31, 2014	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2019
Debt Instrument [Line Items]
Credit Facility, borrowings available									$ 183,500,000
Supplementary leverage ratio					450.00%
Interest coverage ratio					250.00%
Borrowings outstanding under Credit Facility									560,000,000.0
Letter of Credit Facility						$ 40,000,000.0
Outstanding letters of credit , amount						6,500,000			$ 6,500,000
Debt instrument, principal amount						1,575,000,000	$ 696,500,000
Repayments of Debt						$ 36,500,000		$ 81,214,000
NYFRB [Member]
Debt Instrument [Line Items]
Variable margin					1.00%
Maximum [Member] \| Maturity Period 2021 [Member]
Debt Instrument [Line Items]
Unused line of credit commitment fee based on leverage ratio					0.30%
Maximum [Member] \| Maturity Period 2022 [Member]
Debt Instrument [Line Items]
Unused line of credit commitment fee based on leverage ratio					0.40%
Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maturity Period 2021 [Member]
Debt Instrument [Line Items]
Variable margin					2.00%
Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maturity Period 2022 [Member]
Debt Instrument [Line Items]
Variable margin					2.50%
Maximum [Member] \| NYFRB [Member]
Debt Instrument [Line Items]
Consolidated Funded Indebtedness Ratio		2.50%
Maximum [Member] \| NYFRB [Member] \| Maturity Period 2021 [Member]
Debt Instrument [Line Items]
Variable margin					1.00%
Maximum [Member] \| NYFRB [Member] \| Maturity Period 2022 [Member]
Debt Instrument [Line Items]
Variable margin					1.50%
Minimum [Member] \| Maturity Period 2021 [Member]
Debt Instrument [Line Items]
Unused line of credit commitment fee based on leverage ratio					0.15%
Minimum [Member] \| Maturity Period 2022 [Member]
Debt Instrument [Line Items]
Unused line of credit commitment fee based on leverage ratio					0.20%
Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maturity Period 2021 [Member]
Debt Instrument [Line Items]
Variable margin					1.25%
Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maturity Period 2022 [Member]
Debt Instrument [Line Items]
Variable margin					1.50%
Minimum [Member] \| NYFRB [Member]
Debt Instrument [Line Items]
Consolidated Funded Indebtedness Ratio		1.50%
Minimum [Member] \| NYFRB [Member] \| Maturity Period 2021 [Member]
Debt Instrument [Line Items]
Variable margin					0.25%
Minimum [Member] \| NYFRB [Member] \| Maturity Period 2022 [Member]
Debt Instrument [Line Items]
Variable margin					0.50%
Term Loan [Member]
Debt Instrument [Line Items]
Weighted-average interest rate						2.80%
Interest rate of debt instrument						2.80%
Debt instrument, principal amount						$ 665,000,000
Term Loan Agreement [Member]
Debt Instrument [Line Items]
Credit facility, interest rate description						Borrowings under the Term Loan Agreement bear interest, at our option, at a variable rate equal to either (i) the Alternate Base Rate (as defined in the Term Loan Agreement and consistent with the Revolving Credit Facility), plus an agreed spread (ranging from 50 to 150 basis points), or (ii) the Adjusted LIBO Rate (as defined in the Term Loan Agreement) plus an agreed spread (ranging from 150 to 250 basis points), which is established quarterly based on the Company's then Leverage Ratio (as defined in the Term Loan Agreement and consistent with the Revolving Credit Facility). The Company must also maintain a Leverage Ratio and Interest Coverage Ratio consistent with the Revolving Credit Facility.
Term loan facility, unused borrowing capacity, Amount						$ 665,000.0
Term loan Maturity Date						Aug. 02, 2022
Term Loan Agreement [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable margin		1.50%
Term Loan Agreement [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable margin		0.50%
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] \| On or After August 1, 2019 and 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]
Weighted-average interest rate						3.60%	3.40%	2.60%
Interest rate of debt instrument						2.80%	3.80%
Credit Facility, principal balance						$ 500,000,000.0
Credit Facility, borrowings available						750,000,000.0
Credit Facility, available at the end						$ 665,000,000.0
Credit Facility, termination date							Aug. 02, 2022
Credit facility, interest rate description						At the Company’s option, principal amounts outstanding under the Revolving Credit Facility bear interest at a variable rate equal to either (i) the Adjusted LIBO Rate (as defined in the Revolving Credit Facility) plus an agreed spread (ranging from 125 to 200 basis points for loans scheduled to mature in 2021 and from 150 to 250 basis points for loans scheduled to mature in 2022), which is established quarterly based on the Company's then Leverage Ratio; or (ii) an Alternate Base Rate (as defined in the Revolving Credit Facility), which is the highest of (a) the Prime Rate (as defined in the Revolving Credit Facility), (b) the NYFRB (as defined in the Revolving Credit Facility) plus ½ of 1%, and (c) the Adjusted LIBO Rate for a one-month interest period on such day, plus 1.0%, in each case plus an agreed upon spread (ranging from 25 to 100 basis points for loans scheduled to mature in 2021 and from 50 to 150 basis points for loans scheduled to mature in 2022) which is established quarterly based on the Company's then Leverage Ratio.
Debt instrument, principal amount						$ 560,000,000	$ 310,000,000
Revolving Credit Facility [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Credit facility, interest rate description	we further amended the Revolving Credit Facility to, among other things, (i) extend the maturity date with respect to certain lender commitments thereunder from August 2, 2021 to August 2, 2022, (ii) modify the financial covenants to increase the maximum leverage that the Company (on a consolidated basis) is required to maintain, (iii) increase the pricing of borrowings based on the then-existing Leverage Ratio (as defined in the Revolving Credit Facility) which is based on the ratio of the Company’s Consolidated Total Indebtedness (as defined in the Revolving Credit Facility) to Consolidated EBITDA (as defined in the Revolving Credit Facility), and (iv) further restrict the Company and its Restricted Subsidiaries (as defined in the Revolving Credit Facility) from making Restricted Payments (as defined in the Revolving Credit Facility) with certain exceptions, including, among others, no Default (as defined in the Revolving Credit Facility) has occurred and is continuing and based on a pro forma basis after giving effect to any such Restricted Payment the Leverage Ratio would not be greater than 2.50 to 1.00
Revolving Credit Facility [Member] \| Subsequent Event [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Supplementary leverage ratio	250.00%
Revolving Credit Facility [Member] \| Swingline Loan [Member]
Debt Instrument [Line Items]
Credit Facility, principal balance						$ 25,000,000.0
Line of Credit [Member] \| NYFRB [Member]
Debt Instrument [Line Items]
Variable margin					0.50%
Letter of Credit [Member]
Debt Instrument [Line Items]
Unused line of credit commitment fee based on leverage ratio						0.125%