Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Cap rate on an interest rate derivative such as an interest rate cap or collar. If market rates exceed the cap rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

+ Details

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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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

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
Derivative Instruments (Details) - USD ($) $ in Thousands	Jul. 31, 2018	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2017	Feb. 28, 2019
Derivative [Line Items]
Change in fair value of financial instruments			$ (6,395)	$ (6,125)	$ (382)
Interest rate swap agreements
Derivative [Line Items]
Notional amount						$ 500,000
Interest rate swap agreements \| First Lien Loan \| LIBOR
Derivative [Line Items]
Capped interest rate (as a percent)						2.46%
Interest rate cap
Derivative [Line Items]
Capped interest rate (as a percent)		5.75%		5.75%
Strike rate (as a percent)		2.00%		2.00%
Foreign currency forward contract
Derivative [Line Items]
Notional amount		$ 569,200		$ 569,200
Change in fair value of financial instruments	$ (5,700)	(5,100)	$ (5,700)	(5,100)
Designated \| Cash low hedge \| Interest rate cap
Derivative [Line Items]
Notional amount		$ 275,000		$ 275,000