ACCUMULATED OTHER COMPREHENSIVE LOSS - Changes in AOCI by Component (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Changes in AOCI, net of tax by component
Beginning of the period	$ 4,411	$ 4,710
Amounts reclassified to earnings during the year	35	29
Benefit for deferred income taxes	3	40	$ (34)
Other comprehensive income (loss)	(102)	(129)	82
End of the period	3,962	4,411	4,710
Accumulated other comprehensive loss	(665)	(563)
AOCI
Changes in AOCI, net of tax by component
Beginning of the period	(563)	(434)	(484)
Other comprehensive income (loss)	(102)	(129)	82
End of the period	(665)	(563)	(434)
Accumulated other comprehensive loss	(665)	(563)	(434)
Net unrealized investment gains (losses)
Changes in AOCI, net of tax by component
Beginning of the period	0	(14)	(1)
Other comprehensive income (loss)	0	14	(13)
End of the period	0	0	(14)
Net derivative instruments
Changes in AOCI, net of tax by component
Beginning of the period	21	39	(3)
Other comprehensive income (loss), before reclassifications, before tax	26	5	12
Benefit (provision) for deferred income taxes	(7)	(2)	(2)
Reclassification to earnings, tax	9	8	(15)
Reclassification to retained earnings	0	0	2
End of the period	14	21	39
Net derivative instruments \| Foreign currency cash flow hedges
Changes in AOCI, net of tax by component
Amounts reclassified to earnings during the year	(35)	(28)	46
Net derivative instruments \| Interest rate-related derivatives
Changes in AOCI, net of tax by component
Amounts reclassified to earnings during the year	0	(1)	(1)
Amounts Included in Net Periodic Benefit Cost
Changes in AOCI, net of tax by component
Beginning of the period	(253)	(175)	(213)
Other comprehensive income (loss), before reclassifications, before tax	(2)	2	(1)
Benefit (provision) for deferred income taxes	4	25	(15)
Reclassification to earnings, tax	(5)	(3)	(4)
Reclassification to retained earnings	0	0	(34)
End of the period	(244)	(253)	(175)
Net actuarial (gains) losses recognized
Changes in AOCI, net of tax by component
Other comprehensive income (loss), before reclassifications, before tax	(9)	(117)	67
Amounts reclassified to earnings during the year	21	15	19
Net prior service cost (credit) recognized
Changes in AOCI, net of tax by component
Other comprehensive income (loss), before reclassifications, before tax	0	0	5
Amounts reclassified to earnings during the year	0	0	1
Translation adjustments
Changes in AOCI, net of tax by component
Beginning of the period	(331)	(284)	(267)
Other comprehensive income (loss), before reclassifications, before tax	(108)	18	(19)
Amounts reclassified to earnings during the year	2	(77)	0
Benefit for deferred income taxes	2	12	2
End of the period	$ (435)	$ (331)	$ (284)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.

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