Condensed Consolidated Statements of Changes in Common Stockholders' Investment - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2023	Feb. 28, 2022	Feb. 28, 2023	Feb. 28, 2022
Beginning Balance			$ 24,939
Net income	$ 771	$ 1,112	2,434	$ 3,268
Other comprehensive income/(loss), net of tax (expense)/benefit of ($5), ($2), $23, and $3	77	90	(205)	(155)
Ending Balance	24,733	24,526	24,733	24,526
Common Stock
Beginning Balance	32	32	32	32
Ending Balance	32	32	32	32
Additional Paid-In Capital
Beginning Balance	3,487	3,653	3,712	3,481
Purchase of treasury stock	218	(9)	(82)	(9)
Employee incentive plans and other	30	42	105	214
Ending Balance	3,735	3,686	3,735	3,686
Retained Earnings
Beginning Balance	33,557	31,307	32,782	29,817
Net income	771	1,112	2,434	3,268
Cash dividends declared ($1.15, $0.75, $4.60, and $3.00 per share)	(288)	(194)	(1,176)	(792)
Employee incentive plans and other				(68)
Ending Balance	34,040	32,225	34,040	32,225
Accumulated Other Comprehensive Loss
Beginning Balance	(1,385)	(977)	(1,103)	(732)
Other comprehensive income/(loss), net of tax (expense)/benefit of ($5), ($2), $23, and $3	77	90	(205)	(155)
Ending Balance	(1,308)	(887)	(1,308)	(887)
Treasury Stock
Beginning Balance	(11,576)	(9,075)	(10,484)	(8,430)
Purchase of treasury stock	(218)	(1,491)	(1,418)	(2,239)
Employee incentive plans and other	28	36	136	139
Ending Balance	$ (11,766)	$ (10,530)	$ (11,766)	$ (10,530)