v3.26.1
RETIREMENT PLANS - Schedule of Change in Fair Value of Level 3 Assets (Details) - Pension Plan - USD ($)
$ in Millions
 12 Months Ended
May 31, 2026
May 31, 2025
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]    
Balance at beginning of year $ 27,245  
Actual return on plan assets:    
Balance at end of year 29,113 $ 27,245
U.S. Pension Plans    
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]    
Balance at beginning of year 26,601 25,797
Actual return on plan assets:    
Balance at end of year 28,453 26,601
Unobservable
Inputs
Level 3 | U.S. Pension Plans    
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]    
Balance at beginning of year 1,083 1,075
Actual return on plan assets:    
Assets held during current year 11 (63)
Assets sold during the year 100 75
Purchases, sales, and settlements, net (52) (4)
Balance at end of year $ 1,142 $ 1,083