Retirement Benefits - Schedule of Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit Expense (Detail)	12 Months Ended
Nov. 30, 2012	Nov. 30, 2011
Pension Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Discount rate (benefit obligations)	3.68%	4.95%
Discount rate (benefit restoration plan benefit obligations)	3.77%	4.98%
Discount rate (net periodic benefit expense)	4.95%	5.21%
Expected long-term rate of return on plan assets	8.00%	8.00%
Medical and Life Benefits [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Discount rate (benefit obligations)	3.24%	4.58%
Discount rate (net periodic benefit expense)	4.58%	4.65%
Ultimate healthcare trend rate	5.00%	5.00%
Medical and Life Benefits [Member] \| Benefit obligations pre 65/post 65 [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Initial healthcare trend rate	8.75%	9.00%
Year ultimate rate attained	2021	2021
Medical and Life Benefits [Member] \| Net periodic benefit expense pre 65/post 65 [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Initial healthcare trend rate	9.00%	9.00%
Year ultimate rate attained	2021	2021

Defined Benefit Plan, Assumptions Used Calculating Benefit Restoration Plan Obligations, Discount Rate

No definition available.

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- Details

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- Definition

The interest rate used to adjust for the time value of money for the plan.

+ References

+ Details

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- Definition

The interest rate used to adjust for the time value of money.

+ References

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (k)(3)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (l)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

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- Definition

The ultimate trend rate for health care costs.

+ References

+ Details

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- Definition

Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

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