RETIREMENT PENSION PLANS - Rollforward of Pension Liability and Pension Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Change in PBO
Beginning of year	$ 1,728
Actuarial loss (gain)	28
End of year	1,635	$ 1,728
Change in plan assets
Fair value of assets - beginning of year	1,568
Fair value of assets - end of year	1,551	1,568
Pension Plan
Change in PBO
Beginning of year	1,728	1,656
Service cost	0	1	$ 2
Interest cost	53	65	70
Actuarial loss (gain)	(53)	220
Prior service cost	1	0
Benefit payments	(113)	(115)
Foreign currency rate changes	19	(99)
End of year	1,635	1,728	1,656
Change in plan assets
Fair value of assets - beginning of year	1,568	1,547
Actual return on plan assets	66	248
Employer contributions	6	6
Benefit payments	(113)	(115)
Foreign currency rate changes	24	(118)
Fair value of assets - end of year	1,551	1,568	1,547
Funded status	(84)	(160)
U.S. Plans \| Pension Plan
Change in PBO
Beginning of year	1,112	1,042
Service cost	0	0
Interest cost	38	45
Actuarial loss (gain)	(32)	105
Prior service cost	1	0
Benefit payments	(83)	(80)
Foreign currency rate changes	0	0
End of year	1,036	1,112	1,042
Change in plan assets
Fair value of assets - beginning of year	834	830
Actual return on plan assets	65	79
Employer contributions	5	5
Benefit payments	(83)	(80)
Foreign currency rate changes	0	0
Fair value of assets - end of year	821	834	830
Funded status	(215)	(278)
Non-U.S. Plans \| Pension Plan
Change in PBO
Beginning of year	616	614
Service cost	0	1
Interest cost	15	20
Actuarial loss (gain)	(21)	115
Prior service cost	0	0
Benefit payments	(30)	(35)
Foreign currency rate changes	19	(99)
End of year	599	616	614
Change in plan assets
Fair value of assets - beginning of year	734	717
Actual return on plan assets	1	169
Employer contributions	1	1
Benefit payments	(30)	(35)
Foreign currency rate changes	24	(118)
Fair value of assets - end of year	730	734	$ 717
Funded status	$ 131	$ 118

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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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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- Definition

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

+ References

No definition available.

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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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No definition available.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

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- Definition

Amount of foreign currency translation gain (loss) which (increases) decreases benefit obligation of defined benefit plan.

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 60
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-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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