Long-Term Debt - Maturities (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Apr. 30, 2019
Debt maturities
2020 (remaining three months)	$ 10,984
2021	48,475
2022	44,991
2023	39,397
2024	29,670
Thereafter	908,422
Total	1,081,939
First Lien Loan
Debt maturities
2020 (remaining three months)	2,492
2021	9,968
2022	9,968
2023	9,968
2024	9,968
Thereafter	887,031
Total	929,395
Long Term Debt
Unamortized discount	1,777	$ 2,149
Deferred financing costs	9,981	12,072
ABL Facility
Debt maturities
Thereafter	9,806
Total	9,806
Finance lease obligations
Debt maturities
2020 (remaining three months)	7,899
2021	33,633
2022	30,585
2023	25,025
2024	17,921
Thereafter	10,764
Total	125,827
Installment notes
Debt maturities
2020 (remaining three months)	593
2021	4,874
2022	4,438
2023	4,404
2024	1,781
Thereafter	821
Total	16,911
Long Term Debt
Unamortized discount	$ 1,187	$ 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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