Retirement 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, 2022	Sep. 30, 2021	Sep. 30, 2020
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	$ 6,318
Fair value of plan assets, ending	4,533	$ 6,318
Non-U.S. Plans
Change in projected benefit obligation [Roll Forward]
Projected benefit obligation, beginning	1,562	1,633
Service cost	25	29	$ 30
Interest cost	33	32	30
Actuarial (gain) loss	(404)	(101)
Benefits paid	(40)	(39)
Settlements	(29)	(35)
Foreign currency translation and other	(182)	43
Projected benefit obligation, ending	965	1,562	1,633
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	1,474	1,367
Actual return on plan assets	(337)	100
Employer contributions	28	29
Benefits paid	(40)	(39)
Settlements	(29)	(35)
Foreign currency translation and other	(188)	52
Fair value of plan assets, ending	908	1,474	1,367
Net amount recognized in the balance sheet	(57)	(88)
Noncurrent asset	205	283
Current liability	(17)	(16)
Noncurrent liability	(245)	(355)
Pretax accumulated other comprehensive loss	(136)	(182)
U.S. Plans
Change in projected benefit obligation [Roll Forward]
Projected benefit obligation, beginning	4,338	4,525
Service cost	49	54	57
Interest cost	99	94	125
Actuarial (gain) loss	(1,170)	(13)
Benefits paid	(204)	(218)
Settlements	0	(105)
Foreign currency translation and other	0	1
Projected benefit obligation, ending	3,112	4,338	4,525
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	4,844	4,383
Actual return on plan assets	(1,030)	771
Employer contributions	15	12
Benefits paid	(204)	(218)
Settlements	0	(105)
Foreign currency translation and other	0	1
Fair value of plan assets, ending	3,625	4,844	$ 4,383
Net amount recognized in the balance sheet	513	506
Noncurrent asset	676	732
Current liability	(14)	(13)
Noncurrent liability	(149)	(213)
Pretax accumulated other comprehensive loss	$ (284)	$ (274)

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Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as current. Excludes other postretirement benefit plan.

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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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