RETIREMENT PENSION PLANS - Schedule of Balance Sheet Classification of Net Pension Liability (Details) - USD ($) $ in Millions	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Retirement benefits-non-current	$ (336)	$ (262)
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Non-current assets	149	152
Current liabilities	(5)	(5)
Retirement benefits-non-current	(266)	(177)
Net amount recognized	(122)	(30)
U.S. \| Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Non-current assets	0	0
Current liabilities	(5)	(5)
Retirement benefits-non-current	(260)	(173)
Net amount recognized	(265)	(178)
Non-U.S. \| Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Non-current assets	149	152
Current liabilities	0	0
Retirement benefits-non-current	(6)	(4)
Net amount recognized	$ 143	$ 148

Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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