Retirement and Postretirement Benefit Plans- Details of Benefits Expected to be Paid Out (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2013
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	$ 11,531
2016	11,827
2017	11,817
2018	11,737
2019	11,482
2020 - 2024	57,320
Postretirement Benefits Plans [Member] \| Excluding Effect of Medicare Part D Subsidy [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	4,517
2016	4,516
2017	4,515
2018	4,512
2019	4,494
2020 - 2024	21,856
Postretirement Benefits Plans [Member] \| Including Effect of Medicare Part D Subsidy [Member]
Defined Benefit Plan Disclosure [Line Items]
2015	3,878
2016	3,944
2017	4,368
2018	4,374
2019	4,350
2020 - 2024	$ 21,202

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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=28361610&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.

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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

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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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