Retirement and Postretirement Benefit Plans- Details of Benefits Expected to be Paid Out (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 29, 2012
Pension Plans [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2014	$ 11,235
2015	11,507
2016	11,565
2017	11,567
2018	11,566
2019 - 2023	56,629
Postretirement Benefit Plans [Member] \| Excluding Effect of Medicare Part D Subsidy [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2014	4,519
2015	4,528
2016	4,534
2017	4,489
2018	4,464
2019 - 2023	21,737
Postretirement Benefit Plans [Member] \| Including Effect of Medicare Part D Subsidy [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
2014	3,832
2015	3,915
2016	3,864
2017	4,323
2018	4,311
2019 - 2023	$ 20,973

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ 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 (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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- Definition

Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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- Definition

Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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- Definition

Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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- Definition

Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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