Fair Value Measures Fair Value Measures (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Jul. 31, 2016	Jul. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	$ 8,422	$ 2,121
Assets, Fair Value Disclosure, Recurring	8,422	2,121
Financial and Nonfinancial Liabilities, Fair Value Disclosure	668,375	647,571
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	8,422	2,121
Assets, Fair Value Disclosure, Recurring	8,422	2,121
Financial and Nonfinancial Liabilities, Fair Value Disclosure	668,375	647,571
Variable Rate Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Fair Value	0	243,750
Short-term Debt, Fair Value	238,000	0
Variable Rate Debt [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Fair Value	0	243,750
Fixed Rate Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Fair Value	430,375	403,375
Fixed Rate Debt [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Fair Value	430,375	403,375
Other Liabilities [Member] | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	0	446
Other Liabilities [Member] | Interest Rate Swap [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability	$ 0	$ 446