Retirement Plans (Details 12) (USD $) In Millions	May 31, 2011
Pension Plans
Defined Benefit Plan Estimated Future Benefit Payments Abstract
2012	$ 562
2013	633
2014	694
2015	754
2016	843
2017-2021	5,667
Postretirement Healthcare Plans
Defined Benefit Plan Estimated Future Benefit Payments Abstract
2012	31
2013	31
2014	33
2015	35
2016	37
2017-2021	$ 225

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The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph f

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- Definition

The amount of the benefits expected to be paid in Year 5.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph f

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- Definition

The amount of the benefits expected to be paid in Year 4.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph f

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- Definition

The amount of the benefits expected to be paid in Year 1.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph f

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- Definition

The amount of the benefits expected to be paid in Year 3.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph f

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- Definition

The amount of the benefits expected to be paid in Year 2.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph f

+ Details

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