Retirement and Postretirement Benefit Plans- Details of Benefits Expected to be Paid Out (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 28, 2015
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2016	$ 11,322
2017	11,246
2018	11,400
2019	11,443
2020	11,367
2021 - 2025	56,976
Postretirement Benefits Plans Excluding Effect of Medicare Part D Subsidy [Member]
Defined Benefit Plan Disclosure [Line Items]
2016	3,997
2017	3,962
2018	3,942
2019	3,948
2020	3,936
2021 - 2025	19,253
Postretirement Benefits Plans Including Effect of Medicare Part D Subsidy [Member]
Defined Benefit Plan Disclosure [Line Items]
2016	3,424
2017	3,446
2018	3,375
2019	3,336
2020	3,271
2021 - 2025	$ 18,426

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Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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=35743120&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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+ Details

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Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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