Pension and Other Postretirement Benefits (Details) - Pension Benefits [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Oct. 31, 2024	Oct. 31, 2023	Oct. 31, 2024	Oct. 31, 2023
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Sponsor Location [Extensible List]
Service cost	$ 4	$ 5	$ 8	$ 9
Interest cost	9	8	18	17
Expected return on plan assets	(10)	(10)	(19)	(19)
Amortization of net actuarial loss (gain)	1	2	1	3
Net cost	$ 4	$ 5	$ 8	$ 10