Stockholders' Equity (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Oct. 31, 2025	Jul. 31, 2025	Oct. 31, 2024	Jul. 31, 2024	Oct. 31, 2025	Oct. 31, 2024
Beginning balance	$ 3,988	$ 3,993	$ 3,465	$ 3,517	$ 3,993	$ 3,517
Net income	224	170	258	195	394	453
Net other comprehensive income (loss)	14	36	(27)	(43)	50	(70)
Declaration of cash dividends		(214)		(206)
Acquisition of treasury stock	(100)
Stock-based compensation expense	8	4	9	4
Stock issued under compensation plans		5		3
Loss on issuance of treasury stock issued under compensation plans		(6)		(5)
Ending balance	4,134	3,988	3,705	3,465	4,134	3,705
Additional Paid-in Capital [Member]
Beginning balance	34	36	12	13	36	13
Stock-based compensation expense	8	4	9	4
Loss on issuance of treasury stock issued under compensation plans		(6)		(5)
Ending balance	42	34	21	12	42	21
Retained Earnings [Member]
Beginning balance	4,666	4,710	4,250	4,261	4,710	4,261
Net income	224	170	258	195
Declaration of cash dividends		(214)		(206)
Loss on issuance of treasury stock issued under compensation plans
Ending balance	4,890	4,666	4,508	4,250	4,890	4,508
AOCI Attributable to Parent [Member]
Beginning balance	(184)	(220)	(264)	(221)	(220)	(221)
Net other comprehensive income (loss)	14	36	(27)	(43)	50
Ending balance	(170)	(184)	(291)	(264)	(170)	(291)
Treasury Stock, Common [Member]
Beginning balance	(600)	(605)	(605)	(608)	(605)	(608)
Acquisition of treasury stock	100
Stock issued under compensation plans		5		3
Ending balance	(700)	(600)	(605)	(605)	(700)	(605)
Common stock, Class A, voting [Member] | Common Stock [Member]
Beginning balance	25	25	25	25	25	25
Ending balance	25	25	25	25	25	25
Common stock, Class B, nonvoting [Member] | Common Stock [Member]
Beginning balance	47	47	47	47	47	47
Ending balance	$ 47	$ 47	$ 47	$ 47	$ 47	$ 47