POSTRETIREMENT BENEFITS AND EMPLOYEE STOCK OWNERSHIP PLAN - Components Of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Pension Benefits
AMOUNTS RECOGNIZED IN NET PERIODIC BENEFIT COST/(CREDIT)
Service cost	$ 173	$ 164	$ 173
Interest cost	498	527	430
Expected return on plan assets	(657)	(610)	(591)
Amortization of net actuarial loss/(gain)	63	95	133
Amortization of prior service cost/(credit)	40	37	26
Amortization of net actuarial loss/(gain) due to settlements	5	(13)	0
Special termination benefits	3	4	5
NET PERIODIC BENEFIT COST/(CREDIT)	126	203	176
CHANGE IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN AOCI
Net actuarial loss/(gain) - current year	68	(458)
Prior service cost/(credit) - current year	12	21
Amortization of net actuarial (loss)/gain	(63)	(95)
Amortization of prior service (cost)/credit	(40)	(37)
Amortization of net actuarial (loss)/gain due to settlements	(5)	13
Currency translation and other	74	(21)
TOTAL CHANGE IN AOCI	46	(576)
NET AMOUNTS RECOGNIZED IN PERIODIC BENEFIT COST/(CREDIT) AND AOCI	171	(373)
Other Retiree Benefits
AMOUNTS RECOGNIZED IN NET PERIODIC BENEFIT COST/(CREDIT)
Service cost	61	68	71
Interest cost	147	157	142
Expected return on plan assets	(745)	(687)	(611)
Amortization of net actuarial loss/(gain)	(59)	(38)	(7)
Amortization of prior service cost/(credit)	(128)	(127)	(125)
Amortization of net actuarial loss/(gain) due to settlements	0	0	0
Special termination benefits	2	3	4
NET PERIODIC BENEFIT COST/(CREDIT)	(721)	(623)	$ (526)
CHANGE IN PLAN ASSETS AND BENEFIT OBLIGATIONS RECOGNIZED IN AOCI
Net actuarial loss/(gain) - current year	1,592	(366)
Prior service cost/(credit) - current year	(4)	2
Amortization of net actuarial (loss)/gain	59	38
Amortization of prior service (cost)/credit	128	127
Amortization of net actuarial (loss)/gain due to settlements	0	0
Currency translation and other	(14)	(2)
TOTAL CHANGE IN AOCI	1,761	(201)
NET AMOUNTS RECOGNIZED IN PERIODIC BENEFIT COST/(CREDIT) AND AOCI	$ 1,040	$ (824)