Long-Term Debt - Components (Details) - USD ($) $ in Thousands	Apr. 30, 2021	Apr. 22, 2021	Apr. 30, 2020
Debt Instrument [Line Items]
Long-term debt, gross	$ 989,386
Finance lease obligations	117,948		$ 128,767
Carrying value of debt	978,427		1,097,480
Less current portion	46,018		50,201
Long-term debt	932,409		1,047,279
Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	509,722	$ 511,000	876,903
Unamortized discount and deferred financing costs	(4,735)		(10,602)
ABL Facility
Debt Instrument [Line Items]
Long-term debt, gross	0		80,000
Senior Notes
Debt Instrument [Line Items]
Long-term debt, gross	350,000		0
Unamortized discount and deferred financing costs	(5,485)		0
Interest rate		4.625%
Installment notes
Debt Instrument [Line Items]
Long-term debt, gross	11,716		16,316
Unamortized discount	$ (739)		$ (1,098)
Installment notes \| Maximum
Debt Instrument [Line Items]
Interest rate	5.00%		5.00%
Canadian Facility
Debt Instrument [Line Items]
Long-term debt, gross	$ 0		$ 7,194

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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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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Amount of long-term debt and lease obligation, including portion classified as current.

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