SEGMENTS - Geographic Information (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Segment Information
Revenue	$ 15,092.0	$ 15,057.0	$ 16,052.0
Property and equipment, net	2,517.0	2,570.0
Operating right-of-use assets, net	853.0	731.0
United States.
Segment Information
Revenue	3,784.0	3,876.0	4,295.0
Property and equipment, net	877.0	883.0
Operating right-of-use assets, net	179.0	134.0
Belgium
Segment Information
Operating right-of-use assets, net	87.0	92.0
France
Segment Information
Operating right-of-use assets, net	84.0	81.0
Italy
Segment Information
Operating right-of-use assets, net	82.0	76.0
Japan.
Segment Information
Revenue	2,284.0	2,358.0	2,344.0
Other countries, excluding United States and Japan
Segment Information
Revenue	9,024.0	8,823.0	$ 9,413.0
Other countries excluding United States
Segment Information
Property and equipment, net	1,640.0	1,687.0
Other countries excluding United States, Belgium, France, and Italy
Segment Information
Operating right-of-use assets, net	$ 420.0	$ 349.0

Amount of lessee's right to use underlying asset under operating lease.

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