Pension and Other Postretirement Benefits (Plans with PBO in Excess of Plan Assets) (Details) - USD ($) $ in Millions	Apr. 30, 2025	Apr. 30, 2024	Apr. 30, 2023
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Total, Plan Assets	$ 576	$ 576
Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation	(138)	(135)
Defined Benefit Plan, Pension Plan with Plan Assets in Excess of Projected Benefit Obligation, Projected Benefit Obligation	(545)	(544)
Defined Benefit Plan, Benefit Obligation	(683)	(679)	$ (731)
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets	0	0
Defined Benefit Plan, Pension Plan with Plan Assets in Excess of Projected Benefit Obligation, Plan Assets	576	576
Total, Plan Assets	$ 576	$ 576	$ 606

Defined Benefit Plan, Pension Plan with Plan Assets in Excess of Projected Benefit Obligation, Plan Assets

No definition available.

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- Definition

Defined Benefit Plan, Pension Plan with Plan Assets in Excess of Projected Benefit Obligation, Projected Benefit Obligation

+ References

No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
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- Definition

Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

+ Details

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- Definition

Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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