Pension and Other Postretirement Benefits (Expected Benefit Payments) (Details) $ in Millions	Apr. 30, 2018 USD ($)
Pension Benefits [Member]
Expected benefit payments over the next 10 years
2019	$ 57
2020	58
2021	59
2022	61
2023	62
2024-2028	322
Medical and Life Insurance Benefits [Member]
Expected benefit payments over the next 10 years
2019	3
2020	3
2021	3
2022	3
2023	3
2024-2028	$ 17

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- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ 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=82843861&loc=d3e1928-114920

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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

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