SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - ADDITIONAL INFORMATION (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018
Payments to Customers [Member] | Selling, General and Administrative Expenses [Member]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		$ 77	$ 309
Customer and Consumer Promotional Spending [Member] | Retained Earnings [Member]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 534
Reclassification from AOCI to Retained Earnings for Tax Effects [Domain] | Retained Earnings [Member]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	326
Reclassification from AOCI to Retained Earnings for Tax Effects [Domain] | Other Comprehensive Income (Loss)
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ (326)