Long-Term Debt - Components (Details) - USD ($) $ in Thousands	Jan. 31, 2019	Apr. 30, 2018
Long-term debt
Carrying value of debt	$ 1,233,850	$ 595,886
Less current portion	40,328	16,284
Long-term debt	1,193,522	579,602
First Lien Term Loan Due 2025
Long-term debt
Carrying value of debt	974,555	563,179
Unamortized discount	2,238	2,536
Deferred financing costs	12,570	6,125
ABL Facility
Long-term debt
Carrying value of debt	137,898
Capital Lease Obligations
Long-term debt
Carrying value of debt	105,489	18,564
Installment notes
Long-term debt
Carrying value of debt	15,908	14,143
Unamortized discount	$ 1,273	$ 1,534
Installment notes \| Maximum
Long-term debt
Interest rate	5.00%	5.00%

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

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Amount of long-term debt and capital lease obligations including current maturities.

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