POSTRETIREMENT BENEFITS AND EMPLOYEE STOCK OWNERSHIP PLAN - COMPONENTS OF NET PERIODIC BENEFIT COST (Details) - USD ($) $ in Millions		12 Months Ended
		Jun. 30, 2017		Jun. 30, 2016		Jun. 30, 2015
Pension Plan
AMOUNTS RECOGNIZED IN NET PERIODIC BENEFIT COST
Defined Benefit Plan, Service Cost	[2]	$ 310	[1]	$ 314	[1]	$ 317
Defined Benefit Plan, Interest Cost		300	[1]	466	[1]	545
Defined Benefit Plan, Expected Return on Plan Assets		(675)		(731)		(732)
Defined Benefit Plan, Amortization of Gains (Losses)		375		265		275
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)		28		29		30
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements and Curtailments		(186)	[3]	0		0
Defined Benefit Plan, Other Costs		4		6		11
Defined Benefit Plan Gross Periodic Benefit Cost		528		349		446
Employee Stock Ownership Plan (ESOP), Dividends on ESOP Preferred Stock		0		0		0
Defined Benefit Plan, Net Periodic Benefit Cost		528		349		446
CHANGE IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN AOCI
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, before Tax		(852)		2,028
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost (Credit) Arising During Period, before Tax		2		8
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax		(375)		(265)
Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax		(28)		(29)
Other Comprehensive Income Defined Benefit Plan Settlement And Curtailment Cost Before Tax		(186)		0
Other Comprehensive Income, Defined Benefit Plan, Actuarial Gain/(Loss) from Curtailment, Before Tax		(132)		0
Other Comprehensive Income, Defined Benefit Plan, Currency Translation and Other, Before Tax		6		(172)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax		(1,565)		1,570
Defined Benefit Plans, Amount Recognized In Periodic Benefit Cost And Accumulated Other Comprehensive Income		(1,037)		1,919
Other Retiree Benefits
AMOUNTS RECOGNIZED IN NET PERIODIC BENEFIT COST
Defined Benefit Plan, Service Cost	[2]	133	[4]	124	[4]	156
Defined Benefit Plan, Interest Cost		175	[4]	219	[4]	240
Defined Benefit Plan, Expected Return on Plan Assets		(431)		(416)		(406)
Defined Benefit Plan, Amortization of Gains (Losses)		122		78		105
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)		(45)		(52)		(20)
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements and Curtailments		(16)	[3]	0		0
Defined Benefit Plan, Other Costs		21	[3]	12		23
Defined Benefit Plan Gross Periodic Benefit Cost		(9)		(35)		98
Employee Stock Ownership Plan (ESOP), Dividends on ESOP Preferred Stock		45		52		58
Defined Benefit Plan, Net Periodic Benefit Cost		(54)		(87)		$ 40
CHANGE IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN AOCI
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, before Tax		(259)		597
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost (Credit) Arising During Period, before Tax		0		(40)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax		(122)		(78)
Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax		45		52
Other Comprehensive Income Defined Benefit Plan Settlement And Curtailment Cost Before Tax		(16)		0
Other Comprehensive Income, Defined Benefit Plan, Actuarial Gain/(Loss) from Curtailment, Before Tax		(37)		0
Other Comprehensive Income, Defined Benefit Plan, Currency Translation and Other, Before Tax		2		(3)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax		(387)		528
Defined Benefit Plans, Amount Recognized In Periodic Benefit Cost And Accumulated Other Comprehensive Income		$ (441)		$ 441

[1] Primarily non-U.S.-based defined benefit retirement plans.

[2] Service cost includes amounts related to discontinued operations, which are not material for any period.

[3] Amortization of net actuarial loss / prior service cost due to settlement and curtailments and $18 of the special termination benefits are included in Net earnings from discontinued operations.

[4] Primarily U.S.-based other postretirement benefit plans.