Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2013	Apr. 30, 2012
Income Taxes [Abstract]
Effective tax rate	29.80%	29.00%	29.20%	28.00%
Recognized income from statute of limitations expiration	$ 1.8
Adjustment from settlements of tax audits	4.3		4.3
Unrecognized tax benefits	19.4		19.4
Accrued interest and penalties on unrecognized tax benefits	1.2		1.2
Statute of limitations period, average, years			5 years
Maximum possible reduction in amount of unrecognized tax benefits			1.1
Unrecognized tax benefits potential expiration period			12 months
Unrecognized tax benefits in dispute with various taxing authorities	$ 0.2		$ 0.2

Income Tax Examination, Statute Of Limitation Expiration, Recognition Of Income

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- Definition

Maximum Reduction In Amount Of Unrecognized Tax Benefits, Resulting From Lapse Of Statute Of Limitations

+ References

No definition available.

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- Definition

Statutes Of Limitations Period For Unrecognized Tax Benefits

+ References

No definition available.

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- Definition

Unrecognized Tax Benefits In Dispute With Taxing Authorities

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No definition available.

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- Definition

Unrecognized Tax Benefits Potentially Expiration Date.

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No definition available.

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 2

-Article 4

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

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-Name Accounting Standards Codification

-Topic 740

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-Section 50

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(2))

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- Definition

The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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- Definition

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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-Name Accounting Standards Codification

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-SubTopic 10

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-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 21

-Subparagraph a

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- Definition

This element represents the total of accruals as of the date of the statement of financial position for interest recognized for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity and the amount of statutory penalties for a tax position claimed or expected to be claimed by the entity, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.

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-Name FASB Interpretation (FIN)

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