PENSION AND POST-RETIREMENT BENEFIT PLANS - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Pension Plans | U.S.
Components of net periodic benefit cost:
Service cost	$ 37	$ 37	$ 32
Interest cost	33	30	33
Expected return on plan assets	(53)	(52)	(49)
Amortization of:
Actuarial loss	14	16	11
Prior service cost		1	1
Net periodic benefit cost	$ 31	$ 32	$ 28
Weighted-average assumptions used to determine net periodic benefit cost for the year ended June 30:
Expected return on assets (as a percent)	7.00%	7.00%	7.00%
Pension Plans | U.S. | Minimum
Weighted-average assumptions used to determine benefit obligations at June 30:
Discount rate (as a percent)	4.10%	3.40%	3.00%
Rate of compensation increase (as a percent)	2.50%	3.00%	3.00%
Weighted-average assumptions used to determine net periodic benefit cost for the year ended June 30:
Discount rate (as a percent)	3.40%	3.00%	3.70%
Rate of compensation increase (as a percent)	3.00%	3.00%	3.00%
Pension Plans | U.S. | Maximum
Weighted-average assumptions used to determine benefit obligations at June 30:
Discount rate (as a percent)	4.30%	3.90%	3.70%
Rate of compensation increase (as a percent)	8.00%	7.00%	7.00%
Weighted-average assumptions used to determine net periodic benefit cost for the year ended June 30:
Discount rate (as a percent)	3.90%	3.70%	4.40%
Rate of compensation increase (as a percent)	7.00%	7.00%	7.00%
Pension Plans | International
Components of net periodic benefit cost:
Service cost	$ 30	$ 28	$ 25
Interest cost	13	11	15
Expected return on plan assets	(15)	(16)	(20)
Amortization of:
Actuarial loss	5	11	11
Prior service cost		2	2
Special termination benefits	1	2	1
Net periodic benefit cost	$ 34	$ 38	$ 34
Pension Plans | International | Minimum
Weighted-average assumptions used to determine benefit obligations at June 30:
Discount rate (as a percent)	0.50%	0.50%	0.25%
Rate of compensation increase (as a percent)	1.00%	1.00%	0.00%
Weighted-average assumptions used to determine net periodic benefit cost for the year ended June 30:
Discount rate (as a percent)	0.50%	0.25%	0.75%
Expected return on assets (as a percent)	1.75%	1.50%	2.00%
Rate of compensation increase (as a percent)	1.00%	0.00%	1.00%
Pension Plans | International | Maximum
Weighted-average assumptions used to determine benefit obligations at June 30:
Discount rate (as a percent)	7.50%	6.75%	6.00%
Rate of compensation increase (as a percent)	5.50%	5.50%	5.50%
Weighted-average assumptions used to determine net periodic benefit cost for the year ended June 30:
Discount rate (as a percent)	6.75%	6.00%	7.00%
Expected return on assets (as a percent)	6.75%	6.00%	7.00%
Rate of compensation increase (as a percent)	5.50%	5.50%	5.50%
Other than Pension Plans Post-retirement
Components of net periodic benefit cost:
Service cost	$ 3	$ 3	$ 3
Interest cost	7	7	7
Expected return on plan assets	(3)	(1)	(2)
Amortization of:
Actuarial loss		1
Prior service cost	1		1
Net periodic benefit cost	$ 8	$ 10	$ 9
Weighted-average assumptions used to determine net periodic benefit cost for the year ended June 30:
Expected return on assets (as a percent)	7.00%	7.00%	7.00%
Other than Pension Plans Post-retirement | Minimum
Weighted-average assumptions used to determine benefit obligations at June 30:
Discount rate (as a percent)	3.75%	3.70%	3.50%
Weighted-average assumptions used to determine net periodic benefit cost for the year ended June 30:
Discount rate (as a percent)	3.70%	3.50%	4.25%
Other than Pension Plans Post-retirement | Maximum
Weighted-average assumptions used to determine benefit obligations at June 30:
Discount rate (as a percent)	9.75%	9.75%	9.50%
Weighted-average assumptions used to determine net periodic benefit cost for the year ended June 30:
Discount rate (as a percent)	9.75%	9.50%	9.00%