Face (par) amount of debt instrument at time of issuance.

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- 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.

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- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
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-Paragraph 1
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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

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- Definition

The cash inflow from the additional capital contribution to the entity.

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- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

+ References

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- Definition

The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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- Definition

The cash outflow for a borrowing supported by a written promise to pay an obligation.

+ References

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- Definition

Decrease in deferred financing costs due to refunds received.

+ References

No definition available.

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Debt (Bridge Credit Facility) - Additional Information (Detail) - USD ($)					6 Months Ended	12 Months Ended
	Sep. 24, 2019	Sep. 23, 2019	Sep. 10, 2019	Jul. 31, 2019	Sep. 30, 2019	Mar. 31, 2021	Mar. 31, 2020
Debt Instrument [Line Items]
Repayment of borrowings						$ 100,000,000	$ 177,900,000
Repayment of notes							1,300,000,000
Proceeds from Senior Notes							350,000,000
Principal payment from common stock offering			$ 300,000,000.0				$ 293,648,000
5.0% Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Aggregate principal amount		$ 350,000,000.0
Deferred financing fees capitalized		2,100,000
Bridge Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowings permitted under credit facility				$ 350,000,000
Amount borrowed				145,000,000
Letter of Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowings permitted under credit facility	$ 50,000,000			50,000,000
Sublimit of Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowings permitted under credit facility	50,000,000			50,000,000
Bridge Credit Facility [Member]
Debt Instrument [Line Items]
Repayment of borrowings			$ 300,000,000.0
Deferred financing fees capitalized				46,900,000
Decrease in deferred financing costs due to refunds received				14,900,000
Senior Secured Credit Facility
Debt Instrument [Line Items]
Proceeds from Senior Notes	700,000,000.0
Deferred financing fees capitalized	$ 400,000
Bridge Loan Facility [Member]
Debt Instrument [Line Items]
Aggregate principal amount				1,300,000,000
Amount borrowed				$ 1,300,000,000
Repayment of notes		300,000,000.0
Bridge Loan Facility [Member] \| 5.0% Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Repayment of notes		300,000,000.0
Proceeds from Senior Notes		$ 300,000,000.0			$ 350,000,000.0