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

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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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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Nominal or face amount used to calculate payments on the derivative liability.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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Derivative Instruments and Hedging Activities (Details) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2021	Jul. 31, 2020	Apr. 30, 2021
Derivative Instruments and Hedging Activities [Abstract]
Total debt outstanding	$ 964,520		$ 821,588
Unamortized debt issuance costs	500		500
Variable rate loans outstanding	965,000
Interest Rate Swaps [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities [Abstract]
Notional amount of derivative liability	400,000		400,000
Interest Rate Swaps [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Interest Expense [Member]
Derivative Instruments and Hedging Activities [Abstract]
Net losses reclassified from Accumulated other comprehensive loss	(1,100)	$ (900)
Interest Rate Swaps [Member] \| Recurring [Member] \| Level 2 [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities [Abstract]
Liabilities of derivative instrument	4,900		$ 5,600
Interest Rate Swaps [Member] \| Recurring [Member] \| Level 2 [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Other Accrued Liabilities [Member]
Derivative Instruments and Hedging Activities [Abstract]
Liabilities of derivative instrument	1,600
Interest Rate Swaps [Member] \| Recurring [Member] \| Level 2 [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Other Long-term Liabilities [Member]
Derivative Instruments and Hedging Activities [Abstract]
Liabilities of derivative instrument	$ 3,300