Long-Term Debt - Maturities (Details) - USD ($) $ in Thousands	Oct. 31, 2019	Apr. 30, 2019
Debt maturities
2020 (remaining six months)	$ 21,098
2021	45,603
2022	41,966
2023	36,373
2024	26,644
Thereafter	941,962
Total	1,113,646
First Lien Loan
Debt maturities
2020 (remaining six months)	4,984
2021	9,968
2022	9,968
2023	9,968
2024	9,968
Thereafter	887,030
Total	931,886
Long Term Debt
Unamortized discount	1,862	$ 2,149
Deferred financing costs	10,460	12,072
ABL Facility
Debt maturities
Thereafter	47,776
Total	47,776
Finance lease obligations
Debt maturities
2020 (remaining six months)	14,981
2021	30,761
2022	27,560
2023	22,001
2024	14,895
Thereafter	6,312
Total	116,510
Installment notes
Debt maturities
2020 (remaining six months)	1,133
2021	4,874
2022	4,438
2023	4,404
2024	1,781
Thereafter	844
Total	17,474
Long Term Debt
Unamortized discount	$ 1,276	$ 1,200

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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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 payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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