Fixed interest rate related to the interest rate derivative.

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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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.

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No definition available.

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- Definition

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

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- Definition

The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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Fair Value Measurements (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Fair Value Measurements (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Jan. 31, 2021	Jan. 31, 2020	Apr. 30, 2020	Feb. 28, 2019
Fair Value Measurements
Impairment charges			$ 1,000
Interest rate swap agreements
Fair Value Measurements
Interest rate swap gains (losses)	$ (2,200)	$ (6,500)
Expected amount of pre-tax net losses will be reclassified from accumulated other comprehensive income (loss) into earnings during the next twelve months		(11,900)
Interest rate swap agreements \| Fair Value, Measurements, Recurring \| Level 2
Fair Value Measurements
Derivative liabilities	24,566	24,566		$ 32,218
Interest rate swap agreements \| Term Loan Facility
Fair Value Measurements
Notional amount					$ 500,000
Interest rate swap agreements \| LIBOR \| Term Loan Facility
Fair Value Measurements
Fixed interest rate					2.46%
Other accrued expenses and current liabilities \| Interest rate swap agreements
Fair Value Measurements
Derivative liabilities	11,900	11,900
Other liabilities \| Interest rate swap agreements
Fair Value Measurements
Derivative liabilities	$ 12,600	$ 12,600