Financing Arrangements - Schedule of long-term debt (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Jul. 31, 2019
Debt Instrument [Line Items]
Total long-term debt, net of unamortized debt issuance costs	$ 975,425	$ 230,851
Current portion of long-term debt	(31,414)	(10,000)
Long-term debt, net of unamortized debt issuance costs and excluding current portion	944,011	220,851
Line of Credit
Debt Instrument [Line Items]
Unamortized debt issuance costs	(9,745)	(2,149)
Interest rate swap
Debt Instrument [Line Items]
Loans outstanding	8,295	0
Revolving credit loan \| Line of Credit
Debt Instrument [Line Items]
Loans outstanding	399,000	43,000
Tranche A term loan \| Line of Credit
Debt Instrument [Line Items]
Loans outstanding	$ 577,875	$ 190,000

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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