Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Jan. 31, 2018	Jan. 31, 2017
Cash flows from operating activities:
Net income	$ 53,052	$ 34,614
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property and equipment	18,021	19,395
Write-off, accretion and amortization of debt discount and deferred financing fees	2,141	9,142
Amortization of intangible assets	31,527	32,084
Provision for losses on accounts and notes receivable	133	(434)
Provision for obsolescence of inventory	113	427
Increase (decrease) in fair value of contingent consideration	195	(388)
Equity-based compensation	1,473	1,669
(Gain) on sale of assets	(648)	(242)
Changes in assets and liabilities net of effects of acquisitions:
Trade accounts and notes receivable	14,545	(3,179)
Inventories	(23,617)	(25,708)
Accounts payable	(5,723)	318
Deferred income taxes	(12,860)	(14,773)
Prepaid expenses and other assets	(1,719)	(1,425)
Accrued compensation and employee benefits	(7,140)	(3,057)
Accrued expenses and liabilities	1,289	(321)
Liabilities to noncontrolling interest holders	(2,000)	908
Income tax receivable / payable	(5,049)	(12,690)
Cash provided by operating activities	63,733	36,340
Cash flows from investing activities:
Purchases of property and equipment	(13,408)	(6,900)
Proceeds from sale of assets	2,374	3,245
Acquisition of businesses, net of cash acquired	(23,568)	(145,976)
Cash used in investing activities	(34,602)	(149,631)
Cash flows from financing activities:
Repayments on the revolving credit facility	(597,092)	(817,598)
Borrowings from the revolving credit facility	493,739	836,507
Payments of principal on long-term debt	(4,332)	(3,381)
Principal repayments of capital lease obligations	(4,530)	(3,819)
Proceeds from issuance of common stock in initial public offering, net of underwriting discounts		156,941
Borrowings from term loan amendment	577,616	481,225
Debt issuance costs on revolving credit facility amendment		(1,342)
Debt issuance costs	(636)	(2,487)
Payments for taxes related to net share settlement of equity awards	(1,441)
Proceeds from exercises of stock options	130
Other financing activities	(591)
Cash (used in) provided by financing activities	(14,753)	104,821
Increase (decrease) in cash and cash equivalents	14,378	(8,470)
Cash and cash equivalents, beginning of period	14,561	19,072
Cash and cash equivalents, end of period	28,939	10,602
Supplemental cash flow disclosures:
Cash paid for income taxes	35,005	39,831
Cash paid for interest	21,192	20,038
Supplemental schedule of noncash activities:
Assets acquired under capital lease	7,953	6,667
Issuance of installment notes associated with equity-based compensation liability awards	11,898	5,353
Second Lien Term Loan due 2022
Cash flows from financing activities:
Repayment of term loan / Repayment of term loan amendment		(160,000)
Second amendment to First Lien Credit Agreement
Cash flows from financing activities:
Repayment of term loan / Repayment of term loan amendment	$ (477,616)	$ (381,225)