Retirement Plans (Details 12) (USD $) In Millions, unless otherwise specified	May 31, 2014
Pension Plans [Member]
Defined Benefit Plan Estimated Future Benefit Payments Abstract
2015	$ 912
2016	870
2017	954
2018	1,015
2019	1,120
2020-2024	7,398
Postretirement Healthcare Plans [Member]
Defined Benefit Plan Estimated Future Benefit Payments Abstract
2015	41
2016	42
2017	44
2018	45
2019	46
2020-2024	$ 267

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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

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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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- 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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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.

+ References

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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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