Commitments and Contingencies - Schedule of Environmental Reserves and Recoveries (Detail) (Reserve for Environmental Costs [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2011
Reserve for Environmental Costs [Member]
Commitment And Contingencies [Line Items]
Estimated recoverable amounts under U.S. government contracts	$ 10.4	$ 23.1	$ 24.3
Charge to consolidated statement of operations	8.4	11.6	8.6
Total environmental reserve additions	$ 18.8	$ 34.7	$ 32.9

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Amount of the estimated recovery from third parties recorded in the period for an individual site that reduces environmental remediation expense.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13296-110859

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 10

-Subparagraph (d)(3)

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, charged to costs and expenses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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Total increases or decreases in allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

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