Retirement and Postretirement Benefit Plans - Summary of Assets of Plans Held in Trust (Detail)	12 Months Ended
Feb. 28, 2013	Feb. 29, 2012
U.S., Pension Plans [Member] \| Equity securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan, assets held in trust	51.00%	51.00%
U.S., Pension Plans [Member] \| Debt securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan, assets held in trust	48.00%	48.00%
U.S., Pension Plans [Member] \| Cash and cash equivalents [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan, assets held in trust	1.00%	1.00%
International, Pension Plans [Member] \| Equity securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan, assets held in trust	33.00%	31.00%
International, Pension Plans [Member] \| Debt securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan, assets held in trust	64.00%	64.00%
International, Pension Plans [Member] \| Cash and cash equivalents [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan, assets held in trust	3.00%	5.00%
U.S., Postretirement Defined Benefit [Member] \| Equity securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan, assets held in trust	27.00%	30.00%
Postretirement benefit plan, target allocation, minimum	15.00%
Postretirement benefit plan, target allocation, maximum	30.00%
U.S., Postretirement Defined Benefit [Member] \| Debt securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan, assets held in trust	69.00%	69.00%
Postretirement benefit plan, target allocation, minimum	65.00%
Postretirement benefit plan, target allocation, maximum	85.00%
U.S., Postretirement Defined Benefit [Member] \| Cash and cash equivalents [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Defined benefit plan, assets held in trust	4.00%	1.00%
Postretirement benefit plan, target allocation, minimum	0.00%
Postretirement benefit plan, target allocation, maximum	15.00%

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Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ 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 (d)(i)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(i)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e2446-114920

+ Details

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- Definition

Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

+ Details

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e2446-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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