Long-Term Debt - Maturities (Details) - USD ($) $ in Thousands	Oct. 31, 2018	Apr. 30, 2018
Debt maturities
2019 (remaining six months)	$ 16,442
2020	38,697
2021	36,972
2022	186,269
2023	27,578
Thereafter	956,068
Total	1,262,026
First Lien Term Loan Due 2025
Debt maturities
2019 (remaining six months)	4,983
2020	9,968
2021	9,968
2022	9,968
2023	9,968
Thereafter	947,000
Total	991,855
Long Term Debt
Unamortized discount	2,329	$ 2,536
Deferred financing costs	13,081	6,125
ABL Facility
Debt maturities
2022	153,470
Total	153,470
Capital Lease Obligations
Debt maturities
2019 (remaining six months)	10,427
2020	24,616
2021	23,194
2022	19,457
2023	14,268
Thereafter	8,219
Total	100,181
Installment notes
Debt maturities
2019 (remaining six months)	1,032
2020	4,113
2021	3,810
2022	3,374
2023	3,342
Thereafter	849
Total	16,520
Long Term Debt
Unamortized discount	$ 1,388	$ 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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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 remainder of the 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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