CONTINGENCIES - Environmental Loss Contingencies by Site (Details) $ in Millions	12 Months Ended
Sep. 30, 2019 USD ($)
Accrual for Environmental Loss Contingencies [Roll Forward]
Environmental Contingencies, beginning balance	$ 17
Payments and other	(6)
Accruals	4
Environmental Contingencies, ending balance	15
Superfund Sites
Accrual for Environmental Loss Contingencies [Roll Forward]
Environmental Contingencies, beginning balance	12
Payments and other	(3)
Accruals	2
Environmental Contingencies, ending balance	11
Non-Superfund Sites
Accrual for Environmental Loss Contingencies [Roll Forward]
Environmental Contingencies, beginning balance	5
Payments and other	(3)
Accruals	2
Environmental Contingencies, ending balance	$ 4

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Amount of expense for newly incurred environmental loss contingencies. Includes, but is not limited to, remediation expense and interest accretion.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of cash outflow to settle environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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