Pension and Other Postretirement Benefits (Funded Status of Plans) (Details) - USD ($) $ in Millions	Apr. 30, 2026	Apr. 30, 2025	Apr. 30, 2024
Funded Status of Plans
Assets	$ 514	$ 576
Pension Benefits [Member]
Funded Status of Plans
Assets	514	576	$ 576
Obligations	(615)	(683)	(679)
Funded status	(101)	(107)
Medical and Life Insurance Benefits [Member]
Funded Status of Plans
Assets	0	0	0
Obligations	(37)	(39)	$ (36)
Funded status	$ (37)	$ (39)

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.

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+ Details