RISK MANAGEMENT ACTIVITIES AND FAIR VALUE MEASUREMENTS - DERIVATIVE NOTIONAL AMOUNTS AND FAIR VALUE (Details) - USD ($) $ in Millions		Dec. 31, 2017	Jun. 30, 2017
Derivatives Not Designated as Hedging Instruments | Foreign Currency Contract
Derivative [Line Items]
Notional Amount		$ 5,374	$ 4,969
Fair Value Asset/(Liability)		(29)	18
Derivatives in Fair Value Hedging Relationships | Interest Rate Contracts
Derivative [Line Items]
Notional Amount	[1]	4,640	4,552
Fair Value Asset/(Liability)	[1]	137	178
Derivatives in Net Investment Hedging Relationships | Foreign Exchange Contract
Derivative [Line Items]
Notional Amount		6,504	6,102
Fair Value Asset/(Liability)		$ (250)	$ (163)

[1] The fair value of the derivative asset/liability directly offsets the cumulative amount of the fair value hedging adjustment included in the carrying amount of the underlying debt obligation. The carrying amount of the underlying debt obligation, net of the fair value adjustment, was $4,755 as of December 31, 2017 and $4,705 as of June 30, 2017, respectively.