RISK MANAGEMENT ACTIVITIES AND FAIR VALUE MEASUREMENTS - AMOUNT OF GAINS AND LOSSES ON OUTSTANDING DERIVATIVES - ADDITIONAL INFORMATION (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Interest Rate Contract \| Fair Value Hedging
Derivative, Gain (Loss) on Derivative, Net	$ 104	$ (106)
Not Designated as Hedging Instrument \| Foreign Exchange Contract
Derivative, Gain (Loss) on Derivative, Net	$ 54	$ (1)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

Name:	us-gaap_DerivativeGainLossOnDerivativeNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration