PENSION AND POSTRETIREMENT PLANS - Reconciliations of Actuarial Present Value of Projected Benefit Obligations and Fair Value of Plan Assets for Defined Benefit Pension Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	$ 4,454
Fair value of plan assets, ending	4,855	$ 4,454
Noncurrent asset	1,194	995
U.S. Plans
Change in projected benefit obligation [Roll Forward]
Projected benefit obligation, beginning	2,934	3,112
Service cost	17	25	$ 49
Interest cost	169	164	99
Actuarial (gain) loss	283	(75)
Curtailments	(4)	(31)
Benefits paid	(205)	(204)
Settlements	(108)	(2)
Acquisitions (Divestitures), net	0	(56)
Foreign currency translation and other	3	1
Projected benefit obligation, ending	3,089	2,934	3,112
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	3,590	3,625
Actual return on plan assets	598	230
Employer contributions	14	14
Benefits paid	(205)	(204)
Settlements	(108)	(2)
Acquisitions (Divestitures), net	0	(74)
Foreign currency translation and other	0	1
Fair value of plan assets, ending	3,889	3,590	3,625
Net amount recognized in the balance sheet	800	656
Noncurrent asset	961	815
Current liability	(14)	(14)
Noncurrent liability	(147)	(145)
Pretax accumulated other comprehensive loss	(243)	(257)
Non-U.S. Plans
Change in projected benefit obligation [Roll Forward]
Projected benefit obligation, beginning	926	965
Service cost	20	20	25
Interest cost	49	50	33
Actuarial (gain) loss	13	(25)
Curtailments	0	0
Benefits paid	(41)	(42)
Settlements	(39)	(70)
Acquisitions (Divestitures), net	6	(46)
Foreign currency translation and other	70	74
Projected benefit obligation, ending	1,004	926	965
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	864	908
Actual return on plan assets	73	(40)
Employer contributions	24	32
Benefits paid	(41)	(42)
Settlements	(39)	(70)
Acquisitions (Divestitures), net	(2)	2
Foreign currency translation and other	87	74
Fair value of plan assets, ending	966	864	$ 908
Net amount recognized in the balance sheet	(38)	(62)
Noncurrent asset	233	180
Current liability	(17)	(17)
Noncurrent liability	(254)	(225)
Pretax accumulated other comprehensive loss	$ (163)	$ (181)