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PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Millions	3 Months Ended
PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Millions	Jun. 30, 2026	Jun. 30, 2025	Mar. 31, 2026
Property, Plant, and Equipment [Line Items]
Total cost	$ 248		$ 242
Less: accumulated depreciation	(105)		(99)
Total net book value	143		143
Depreciation expense	6	$ 7
Equipment
Property, Plant, and Equipment [Line Items]
Total cost	15		11
Furniture and fixtures
Property, Plant, and Equipment [Line Items]
Total cost	45		44
Leasehold improvements
Property, Plant, and Equipment [Line Items]
Total cost	164		165
Computers and software
Property, Plant, and Equipment [Line Items]
Total cost	16		14
Other
Property, Plant, and Equipment [Line Items]
Total cost	$ 8		$ 8