POSTRETIREMENT BENEFITS AND EMPLOYEE STOCK OWNERSHIP PLAN - DEFINED CONTRIBUTION RETIREMENT PLANS (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Cost	$ 317	$ 272	$ 292
UNITED STATES
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan Contribution Rate	14.00%	14.00%	14.00%

Amount of cost for defined contribution plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration