Financing Arrangements - Schedule of long-term debt (Details) - USD ($)	Jul. 31, 2020	Jul. 31, 2019	Jun. 28, 2018
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (4,246,000)
Total long-term debt, net of unamortized debt issuance costs	934,209,000	$ 230,851,000
Current portion of long-term debt	(7,375,000)	(10,000,000)
Long-term debt, net of unamortized debt issuance costs and excluding current portion	926,834,000	220,851,000
Line of Credit
Debt Instrument [Line Items]
Unamortized debt issuance costs	(11,166,000)	(2,149,000)
Revolving credit loan \| Line of Credit
Debt Instrument [Line Items]
Loans outstanding	399,000,000	43,000,000	$ 400,000,000
Tranche A term loan \| Line of Credit
Debt Instrument [Line Items]
Loans outstanding	$ 546,375,000	$ 190,000,000	$ 200,000,000

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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