SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Currency Translation and Transactions (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Currency Translation and Transactions
Unrealized translation gains (losses), net of tax	$ (173)	$ 2	$ (170)	$ (11)
Realized foreign currency gain on liquidation		77
Loss on sale of available-for-sale securities		6
Net exchange gains (losses) on foreign currency transactions	$ 15	$ 73	$ 40	$ 52

Amount after 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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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