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, 2021	Sep. 30, 2020	Sep. 30, 2019
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	$ 5,750
Fair value of plan assets, ending	6,318	$ 5,750
U.S. Plans
Change in projected benefit obligation [Roll Forward]
Projected benefit obligation, beginning	4,525	4,410
Service cost	54	57	$ 47
Interest cost	94	125	155
Actuarial (gain) loss	(13)	260
Benefits paid	(218)	(202)
Settlements	(105)	(111)
Foreign currency translation and other	1	(14)
Projected benefit obligation, ending	4,338	4,525	4,410
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	4,383	4,208
Actual return on plan assets	771	466
Employer contributions	12	20
Benefits paid	(218)	(202)
Settlements	(105)	(111)
Foreign currency translation and other	1	2
Fair value of plan assets, ending	4,844	4,383	4,208
Net amount recognized in the balance sheet	506	(142)
Noncurrent asset	732	140
Current liability	(13)	(11)
Noncurrent liability	(213)	(271)
Pretax accumulated other comprehensive loss	(274)	(937)
Non-U.S. Plans
Change in projected benefit obligation [Roll Forward]
Projected benefit obligation, beginning	1,633	1,584
Service cost	29	30	24
Interest cost	32	30	38
Actuarial (gain) loss	(101)	3
Benefits paid	(39)	(37)
Settlements	(35)	(46)
Foreign currency translation and other	43	69
Projected benefit obligation, ending	1,562	1,633	1,584
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	1,367	1,284
Actual return on plan assets	100	58
Employer contributions	29	46
Benefits paid	(39)	(37)
Settlements	(35)	(46)
Foreign currency translation and other	52	62
Fair value of plan assets, ending	1,474	1,367	$ 1,284
Net amount recognized in the balance sheet	(88)	(266)
Noncurrent asset	283	125
Current liability	(16)	(15)
Noncurrent liability	(355)	(376)
Pretax accumulated other comprehensive loss	$ (182)	$ (316)

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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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