Retirement Plans (Schedule Of Retirement Plans Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Net periodic pension expense	$ 28	$ 67	$ 2
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost (benefits earned during the period)	29	30	24
Interest cost	32	30	38
Expected return on plan assets	(74)	(72)	(68)
Net amortization and other	14	17	6
Net periodic pension expense	1	5	0
Defined contribution plans	52	56	56
Total retirement plans expense	53	61	56
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost (benefits earned during the period)	54	57	47
Interest cost	94	125	155
Expected return on plan assets	(264)	(268)	(281)
Net amortization and other	143	148	81
Net periodic pension expense	27	62	2
Defined contribution plans	114	112	125
Total retirement plans expense	$ 141	$ 174	$ 127