RISK MANAGEMENT ACTIVITIES AND FAIR VALUE MEASUREMENTS - SCHEDULE OF DERIVATIVE INSTRUMENTS (Details) - USD ($) $ in Millions	Mar. 31, 2020	Jun. 30, 2019
Derivative [Line Items]
Derivative, Notional Amount	$ 16,295	$ 17,309
Derivative Asset	348	239
Derivative Liability	(86)	(45)
Derivatives in Fair Value Hedging Relationships \| Interest Rate Contracts
Derivative [Line Items]
Derivative, Notional Amount	7,015	7,721
Derivative Asset	232	177
Derivative Liability	0	(1)
Derivatives in Net Investment Hedging Relationships \| Foreign Exchange Contract
Derivative [Line Items]
Derivative, Notional Amount	3,279	3,157
Derivative Asset	69	35
Derivative Liability	(10)	(24)
Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	10,294	10,878
Derivative Asset	301	212
Derivative Liability	(10)	(25)
Not Designated as Hedging Instrument \| Foreign Exchange Contract
Derivative [Line Items]
Derivative, Notional Amount	6,001	6,431
Derivative Asset	47	27
Derivative Liability	$ (76)	$ (20)

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Nominal or face amount used to calculate payment on derivative.

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