SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Currency Translation and Transactions (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Currency Translation and Transactions
Unrealized translation gains (losses), net of tax	$ (106)	$ 30	$ (17)
Realized foreign currency gain on sale of foreign subsidiary reclassification from AOCI	77
Gross realized loss on sale of securities reclassification from AOCI	6
Net exchange gains (losses) on foreign currency transactions	$ 51	$ 46	$ (95)

Amount before tax of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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