Fair Value Measures (Details) - USD ($) $ in Thousands	Jan. 31, 2016	Jul. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable equity securities	$ 17,465	$ 0
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	2,584	2,121
Marketable equity securities	17,465	0
Total Assets	20,049	2,121
Total Liabilities	686,001	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
Marketable equity securities	17,465
Total Assets	17,465
Total Liabilities	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	2,584	2,121
Marketable equity securities	0	0
Total Assets	2,584	2,121
Total Liabilities	686,001	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	0	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
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	0	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	206,250	243,750
Long-term fixed rate debt, including current portion	206,250	243,750
Revolving loan facility	68,000	0
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
Long-term fixed rate debt, including current portion	0
Revolving loan facility	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	206,250	243,750
Long-term fixed rate debt, including current portion	206,250	243,750
Revolving loan facility		0
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	411,751	403,375
Long-term fixed rate debt, including current portion	411,751	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
Long-term fixed rate debt, including current portion	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	411,751	403,375
Long-term fixed rate debt, including current portion	$ 411,751	$ 403,375