RISK MANAGEMENT ACTIVITIES AND FAIR VALUE MEASUREMENTS - DERIVATIVE INSTRUMENTS, EFFECT ON OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Derivatives in Net Investment Hedging Relationships | Foreign Exchange Contract
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	[1],[2]	$ 83	$ 34	$ 114	$ 53

[1] For the derivatives in net investment hedging relationships, the amount of gain/(loss) excluded from effectiveness testing, which was recognized in earnings, was $17 and $17 for the three months ended March 31, 2020 and 2019, respectively. The amount of gain/(loss) excluded from effectiveness testing was $57 and $44 for the nine months ended March 31, 2020 and 2019, respectively.

[2] In addition to the foreign currency derivative contracts designated as net investment hedges, certain of our foreign currency denominated debt instruments are designated as net investment hedges. The amount of gain/(loss) recognized in Accumulated other comprehensive income/(loss) (AOCI) for such instruments was $306 and $226 for the three months ended March 31, 2020 and 2019, respectively. The amount of gain/(loss) recognized in AOCI for such instruments was $487 and $467 for the nine months ended March 31, 2020 and 2019, respectively.