Fair Values (Narrative) (Details) (USD $)	3 Months Ended
Oct. 31, 2014	Oct. 31, 2013	Jul. 31, 2014
Debt Instrument [Line Items]
Aggregate carrying amount of equity method investments	$ 20,300,000		$ 21,400,000
Impairment charges	0	0
Long-Term Debt [Member]
Debt Instrument [Line Items]
Fair value of debt	239,800,000
Debt carrying amount	$ 225,000,000

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

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