Long-Term Debt - Maturities (Details) - USD ($) $ in Thousands	Jan. 31, 2019	Apr. 30, 2018
Debt maturities
2019 (remaining three months)	$ 8,788
2020	40,674
2021	39,060
2022	172,913
2023	29,571
Thereafter	958,925
Total	1,249,931
First Lien Term Loan Due 2025
Debt maturities
2019 (remaining three months)	2,491
2020	9,968
2021	9,968
2022	9,968
2023	9,968
Thereafter	947,000
Total	989,363
Long Term Debt
Unamortized discount	2,238	$ 2,536
Deferred financing costs	12,570	6,125
ABL Facility
Debt maturities
2022	137,898
Total	137,898
Capital Lease Obligations
Debt maturities
2019 (remaining three months)	5,693
2020	26,343
2021	25,039
2022	21,430
2023	16,019
Thereafter	10,965
Total	105,489
Installment notes
Debt maturities
2019 (remaining three months)	604
2020	4,363
2021	4,053
2022	3,617
2023	3,584
Thereafter	960
Total	17,181
Long Term Debt
Unamortized discount	$ 1,273	$ 1,534

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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