RELATED PARTY TRANSACTIONS - Net Parent Investment (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021
Related Party Transaction [Line Items]
Net Parent investment	$ 7,102	$ 7,102		$ 6,040	$ 6,027
IBM
Related Party Transaction [Line Items]
Net Parent investment	7,000	7,000	$ 0
Amount of transfers from Parent	1,800	2,200
Non-cash transfers from parent	$ 660	820
Net transfers from parent in statement of cash flows		$ 1,300