Pension and Other Postretirement Benefits (Expected Benefit Payments) (Details) $ in Millions	Apr. 30, 2021 USD ($)
Pension Benefits [Member]
Expected benefit payments over the next 10 years
2022	$ 69
2023	66
2024	65
2025	64
2026	66
2027 – 2031	327
Medical and Life Insurance Benefits [Member]
Expected benefit payments over the next 10 years
2022	3
2023	3
2024	3
2025	3
2026	3
2027 – 2031	$ 15

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

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

+ References

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

+ References

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

+ References

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

+ References

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

+ References

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