Long-Term Debt - Components (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Apr. 30, 2017
Long-term debt
Carrying value of debt	$ 597,484	$ 594,920
Less current portion	15,949	11,530
Long-term debt	581,535	583,390
First Lien Term Loan due 2023
Long-term debt
Carrying value of debt	564,141	470,245
Unamortized discount	2,677	1,658
Deferred financing costs	6,466	5,712
ABL Facility
Long-term debt
Carrying value of debt		103,353
Capital lease obligations
Long-term debt
Carrying value of debt	$ 19,034	$ 15,611
Interest rate	5.50%	5.50%
Installment notes
Long-term debt
Carrying value of debt	$ 14,309	$ 5,711
Unamortized discount	$ 1,599	$ 751
Installment notes \| Maximum
Long-term debt
Interest rate	5.00%	5.00%

Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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-Name Accounting Standards Codification
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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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