LEASES - Operating Lease Assets and Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2020	Oct. 01, 2019
Leases [Abstract]
Weighted-average remaining lease term (years)	5 years
Weighted-average discount rate	3.84%
Operating lease assets	$ 326	$ 333
Operating lease liabilities	$ 351	$ 357
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PrepaidExpenseAndOtherAssets
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilities