Income Taxes (Schedule Of Changes In Unrecognized Tax Benefit) (Details) (USD $) In Thousands	12 Months Ended
Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009
Income Taxes
Beginning balance	$ 31,039	$ 30,235	$ 21,032
Increase in liability due to federal benefit			11,031
Tax positions related to prior years: Additions	1,817	760	1,880
Tax positions related to prior years: Reductions	(1,062)	(1,883)
Tax positions related to current year: Additions	3,713	4,095	622
Settlements	(2,642)	(817)	(3,002)
Lapses in statute of limitations	(691)	(1,351)	(1,328)
Ending balance	$ 32,174	$ 31,039	$ 30,235

Gross Amount Of Unrecognized Tax Benefits Excluding Interest and Penalties Pertaining to Uncertain Tax Positions

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- Definition

Unrecognized Tax Benefits Increase In Liability Due To Federal Benefit

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph a(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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
-Paragraph 15A
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph a(2)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

+ References

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The gross amount of increases in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph a(3)
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 50
-Paragraph 15A
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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- Definition

The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 48
-Paragraph 21
-Subparagraph a(4)
-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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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