v3.26.1
RETIREMENT PLANS - Schedule of Net Periodic Benefit Cost (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Feb. 28, 2026
Feb. 28, 2025
Feb. 28, 2026
Feb. 28, 2025
Net Periodic Benefit Cost        
Net periodic benefit cost $ 47 $ 69 $ 140 $ 209
Pension Plans | U.S. Plans        
Net Periodic Benefit Cost        
Service cost 112 125 335 374
Interest cost 378 361 1,135 1,085
Expected return on plan assets (457) (430) (1,371) (1,290)
Amortization of prior service credit and other (2) (2) (6) (6)
Other retirement plans expense (income) (81) (71) (242) (211)
Net periodic benefit cost 31 54 93 163
Pension Plans | International Pension Plans        
Net Periodic Benefit Cost        
Service cost 10 9 30 29
Interest cost 12 10 36 32
Expected return on plan assets (6) (4) (19) (16)
Amortization of prior service credit and other 0 0 0 1
Other retirement plans expense (income) 6 6 17 17
Net periodic benefit cost 16 15 47 46
Postretirement Healthcare Plans        
Net Periodic Benefit Cost        
Service cost 6 6 20 19
Interest cost 17 17 50 49
Expected return on plan assets 0 0 0 0
Amortization of prior service credit and other (1) (1) (3) (3)
Other retirement plans expense (income) 16 16 47 46
Net periodic benefit cost $ 22 $ 22 $ 67 $ 65