RISK MANAGEMENT ACTIVITIES AND FAIR VALUE MEASUREMENTS - SCHEDULE OF DERIVATIVE INSTRUMENTS (Details) - USD ($) $ in Millions	Mar. 31, 2021	Jun. 30, 2020
Derivative [Line Items]
Derivative, Notional Amount	$ 21,077	$ 16,956
Derivative Asset	278	318
Derivative Liability	(162)	(66)
Derivatives in Fair Value Hedging Relationships \| Interest Rate Contracts
Derivative [Line Items]
Derivative, Notional Amount	7,327	7,114
Derivative Asset	174	269
Derivative Liability	0	0
Derivatives in Net Investment Hedging Relationships \| Foreign Exchange Contract
Derivative [Line Items]
Derivative, Notional Amount	7,375	3,856
Derivative Asset	97	26
Derivative Liability	(92)	(41)
Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	14,702	10,970
Derivative Asset	271	295
Derivative Liability	(92)	(41)
Not Designated as Hedging Instrument \| Foreign Exchange Contract
Derivative [Line Items]
Derivative, Notional Amount	6,375	5,986
Derivative Asset	7	23
Derivative Liability	$ (70)	$ (25)

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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