Fair Value Measures (Details) - USD ($) $ in Thousands	Oct. 31, 2015	Jul. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable equity securities	$ 21,893	$ 0
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	2,542	2,121
Marketable equity securities	21,893
Total Assets	24,435	2,121
Total Liabilities	629,961	647,571
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Marketable equity securities	21,893
Total Assets	21,893	0
Total Liabilities	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	2,542	2,121
Total Assets	2,542	2,121
Total Liabilities	629,961	647,571
Other Liabilities [Member] | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap derivative	156	446
Other Liabilities [Member] | Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap derivative	0	0
Other Liabilities [Member] | Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap derivative	156	446
Variable Rate Debt [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term variable rate debt, including current portion	225,000	243,750
Long-term fixed rate debt, including current portion	225,000	243,750
Variable Rate Debt [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term variable rate debt, including current portion	0	0
Long-term fixed rate debt, including current portion	0	0
Variable Rate Debt [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term variable rate debt, including current portion	225,000	243,750
Long-term fixed rate debt, including current portion	225,000	243,750
Fixed Rate Debt [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term variable rate debt, including current portion	404,805	403,375
Long-term fixed rate debt, including current portion	404,805	403,375
Fixed Rate Debt [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term variable rate debt, including current portion	0	0
Long-term fixed rate debt, including current portion	0	0
Fixed Rate Debt [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term variable rate debt, including current portion	404,805	403,375
Long-term fixed rate debt, including current portion	$ 404,805	$ 403,375