Retirement Plans (Details 12) (USD $) In Millions, unless otherwise specified	May 31, 2013
Pension Plans [Member]
Defined Benefit Plan Estimated Future Benefit Payments Abstract
2014	$ 821
2015	956
2016	896
2017	961
2018	1,049
2019-2023	6,974
Postretirement Healthcare Plans [Member]
Defined Benefit Plan Estimated Future Benefit Payments Abstract
2014	39
2015	42
2016	44
2017	45
2018	47
2019-2023	$ 274

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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

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

+ References

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

+ References

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