LONG-TERM DEBT (Letter of Credit Facility) (Details) - USD ($) $ in Millions	Dec. 20, 2015	Sep. 30, 2015	Sep. 30, 2014	Feb. 21, 2014
Debt Instrument [Line Items]
Amount outstanding, letters of credit			$ 9
Standby Letters of Credit
Debt Instrument [Line Items]
Maximum limit on issuance of letters of credit				$ 30
Amount outstanding, letters of credit		$ 24	$ 25
Other Letters of Credit Arrangements
Debt Instrument [Line Items]
Amount outstanding, letters of credit		$ 6
Forecasted | Standby Letters of Credit
Debt Instrument [Line Items]
Maximum limit on issuance of letters of credit	$ 25