Notes Payable And Long-Term Debt (Narrative) (Details) (USD $)	Nov. 30, 2011 7.750% Senior Notes Due 2016 [Member]	Feb. 28, 2011 7.750% Senior Notes Due 2016 [Member]	Nov. 30, 2011 8.250% Senior Notes Due 2018 [Member]	Aug. 31, 2007 8.250% Senior Notes Due 2018 [Member]	Nov. 30, 2011 5.625% Senior Notes Due 2020 [Member]
Debt Instrument [Line Items]
Senior unsecured notes	$ 312,000,000		$ 400,000,000		$ 400,000,000
Senior unsecured notes, interest rate	7.75%	7.75%	8.25%	8.25%	5.625%
Estimated fair value of senior notes	$ 349,400,000		$ 452,000,000		$ 400,800,000

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

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