RISK MANAGEMENT ACTIVITIES AND FAIR VALUE MEASUREMENTS - GAIN (LOSS) ON DERIVATIVE INSTRUMENTS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Not Designated as Hedging Instrument | Foreign Currency Contract
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) Recognized in Earnings	$ (5)	$ (1)	$ (7)	$ (2)
Derivatives in Fair Value Hedging Relationships | Interest Rate Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) Recognized in Earnings	$ 42	$ (38)	$ 18	$ (41)