Description of Business and Summary of Significant Accounting Policies (Details Textual) $ in Millions	9 Months Ended
Apr. 30, 2016 USD ($) Derivative Segment	Jul. 31, 2015 USD ($)
Description Of Business and Summary Of Significant Accounting Policies [Line Items]
Tax benefits realized upon ultimate settlement, Description	The second step is to measure the tax benefit as the largest amount that is more than 50% likely to be realized upon ultimate settlement.
Marketable securities, amortized cost basis	$ 21.1
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds	21.5
Available-for-sale Securities, Gross Realized Gains	0.4
Capitalized Computer Software, Period Increase (Decrease)	29.8
Capitalized software costs	43.8	$ 65.1
Accumulated amortization expense	$ 18.0	$ 42.6
Number of operating segments \| Segment	2
Number of reportable segment \| Segment	1
Interest Rate Swap
Description Of Business and Summary Of Significant Accounting Policies [Line Items]
Number of interest rate derivatives held \| Derivative	2

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
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The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

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For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase (decrease) in capitalized computer software costs.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Description of events or transactions pertaining to income taxes classified as other.

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