Balance Sheet Accounts and Supplemental Disclosures - Schedule of Other Noncurrent Liabilities (Detail) (USD $) In Millions, unless otherwise specified	May 31, 2013	Nov. 30, 2012	Nov. 30, 2011
Schedule Of Other Liabilities [Line Items]
Conditional asset retirement obligations	$ 21.4	$ 20.8	$ 17.8
Pension benefits, non-qualified	18.7	18.9	16.1
Deferred compensation	9.1	8.4	7.8
Deferred revenue	8.3	8.6	9.2
Legal settlements	0.3	2.3	8.3
Other	9.6	9.5	4.9
Other noncurrent liabilities	$ 67.4	$ 68.5	$ 64.1

Defined Benefit Pension Plan Nonqualified

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- Definition

Other Components Of Other Noncurrent Liabilities

+ References

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- Definition

Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

+ References

No definition available.

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- Definition

The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1)

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 8

-Subparagraph (b)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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Carrying amount of estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid after one year or beyond the normal operating cycle, if longer.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.25)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 25

-Article 5

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Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer).

+ References

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-Name Accounting Standards Codification

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-Number 210

-Section 02

-Paragraph 24

-Article 5

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