Stock-Based Compensation Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Apr. 30, 2024	Apr. 30, 2023	Apr. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax compensation expense	$ 25	$ 18	$ 15
Deferred tax benefit	3	3	2
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 14
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 7 months 6 days
Intrinsic value of SSARs exercised	$ 12	19	23
Fair value of shares vested	4	6	7
Excess tax benefit from exercise / vesting of awards	$ 2	$ 4	$ 6