Fair Value Measures (Details) - USD ($) $ in Thousands	Oct. 31, 2020	Jul. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$ 411,149	$ 11,483
Total Liabilities	399,707	399,698
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents, at Carrying Value	411,149	11,483
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	411,159	11,483
Assets, Fair Value Disclosure	411,159	11,483
Total Liabilities	441,373	449,731
Fixed Rate Debt | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	399,707	399,698
Fixed Rate Debt | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term variable rate debt, including current portion	441,373	449,731
Long-term fixed rate debt, including current portion	$ 441,373	$ 449,731