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, 2015	Sep. 30, 2014	Sep. 30, 2013
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	$ 5,461
Fair value of plan assets, ending	4,863	$ 5,461
Noncurrent asset	33	377
Noncurrent liability	(662)	(564)
U.S. Plans [Member]
Change in projected benefit obligation [Roll Forward]
Projected benefit obligation, beginning	4,336	3,863
Service cost	69	59	$ 70
Interest cost	182	182	167
Actuarial (gain) loss	137	415
Benefits paid	(181)	(174)
Settlements	(205)	(14)
Acquisitions (Divestitures), net	(70)	0
Foreign currency translation and other	(5)	5
Projected benefit obligation, ending	4,263	4,336	3,863
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	4,473	4,112
Actual return on plan assets	(137)	461
Employer contributions	20	85
Benefits paid	(181)	(174)
Settlements	(205)	(14)
Acquisitions (Divestitures), net	(44)	0
Foreign currency translation and other	2	3
Fair value of plan assets, ending	3,928	4,473	4,112
Net amount recognized in the balance sheet	(335)	137
Noncurrent asset	1	344
Current liability	(11)	(10)
Noncurrent liability	(325)	(197)
Pretax accumulated other comprehensive loss	(1,322)	(961)
Non-U.S. Plans [Member]
Change in projected benefit obligation [Roll Forward]
Projected benefit obligation, beginning	1,330	1,269
Service cost	37	32	31
Interest cost	46	53	46
Actuarial (gain) loss	44	89
Benefits paid	(36)	(36)
Settlements	(25)	(14)
Acquisitions (Divestitures), net	(4)	(28)
Foreign currency translation and other	(144)	(35)
Projected benefit obligation, ending	1,248	1,330	1,269
Change in fair value of plan assets [Roll Forward]
Fair value of plan assets, beginning	988	899
Actual return on plan assets	49	106
Employer contributions	33	45
Benefits paid	(36)	(36)
Settlements	(25)	(14)
Acquisitions (Divestitures), net	(2)	0
Foreign currency translation and other	(72)	(12)
Fair value of plan assets, ending	935	988	$ 899
Net amount recognized in the balance sheet	(313)	(342)
Noncurrent asset	32	33
Current liability	(8)	(8)
Noncurrent liability	(337)	(367)
Pretax accumulated other comprehensive loss	$ (306)	$ (346)

Defined Benefit Plan, Acquisitions and Divestitures, Net

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Fair Value of Plan Assets, Acquisitions and Divestitures, Net

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Fair Value of Plan Assets, Foreign Currency Translation And Other

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Projected benefit obligation, foreign currency translation and other.

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This represents the current liability recognized in the balance sheet that is associated with the defined benefit pension plans.

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This represents the noncurrent liability recognized in the balance sheet that is associated with the defined benefit pension plans.

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The pretax total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)

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-Glossary Actual Return on Plan Assets (Component of Net Periodic Pension Cost)

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Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

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The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

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The amount for overfunded plans recognized in the balance sheet as a noncurrent asset associated with a defined benefit pension plan or other postretirement defined benefit plan.

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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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-Glossary Benefits

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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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The increase in the fair value of plan assets from contributions made by the employer.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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The amount of decrease that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts.

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The amount that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts.

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