Income Taxes (Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Apr. 30, 2024	Apr. 30, 2023	Apr. 30, 2022
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Unrecognized tax benefits at beginning of year	$ 21	$ 14	$ 12
Additions for tax positions provided in prior periods	1	8	2
Additions for tax positions provided in current period	2	3	2
Decreases for tax positions provided in prior years	(3)	0	0
Settlements of tax positions in the current period	(3)	0	0
Lapse of statutes of limitations	(4)	(4)	(2)
Unrecognized tax benefits at end of year	14	$ 21	$ 14
Unrecognized Tax Benefits [Abstract]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	11
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	$ 0