Long-Term Debt - Maturities (Details) - USD ($) $ in Thousands	Jul. 31, 2018	Apr. 30, 2018
Debt maturities
2019 (remaining nine months)	$ 24,617
2020	41,351
2021	37,092
2022	247,610
2023	20,785
Thereafter	949,661
Total	1,321,116
First Lien Term Loan Due 2025
Debt maturities
2019 (remaining nine months)	7,476
2020	9,968
2021	9,968
2022	9,968
2023	9,968
Thereafter	947,000
Total	994,348
Long Term Debt
Unamortized discount	2,420	$ 2,536
Deferred financing costs	13,594	6,125
ABL Facility
Debt maturities
2022	215,401
Total	215,401
Capital Lease Obligations
Debt maturities
2019 (remaining nine months)	13,597
2020	27,589
2021	23,634
2022	19,186
2023	7,794
Thereafter	1,886
Total	93,686
Installment notes
Debt maturities
2019 (remaining nine months)	3,544
2020	3,794
2021	3,490
2022	3,055
2023	3,023
Thereafter	775
Total	17,681
Long Term Debt
Unamortized discount	$ 1,462	$ 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 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 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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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 in the third 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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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 in the second 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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