Retirement Plans - Schedule of Net Periodic Benefit (Income) Cost (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2024	May 31, 2023	May 31, 2022
Pension Plans [Member] | U.S. Plans [Member]
Net Periodic Benefit Cost
Service cost	$ 544	$ 651	$ 835
Interest cost	1,362	1,218	1,020
Expected return on plan assets	(1,598)	(1,688)	(1,910)
Amortization of prior service credit	(7)	(7)	(7)
Actuarial (gains) losses and other	(590)	(487)	1,683
Net periodic benefit (income) cost	(289)	(313)	1,621
Pension Plans [Member] | International Pension Plans [Member]
Net Periodic Benefit Cost
Service cost	38	44	56
Interest cost	42	34	32
Expected return on plan assets	(18)	(14)	(26)
Amortization of prior service credit		(2)	(2)
Actuarial (gains) losses and other	13	(25)	87
Net periodic benefit (income) cost	75	37	147
Postretirement Healthcare Plans [Member]
Net Periodic Benefit Cost
Service cost	27	37	48
Interest cost	61	55	41
Amortization of prior service credit	(3)
Actuarial (gains) losses and other	16	(138)	(192)
Net periodic benefit (income) cost	$ 101	$ (46)	$ (103)