SEGMENTS - Reconciliation of consolidated pretax income (loss) to segment adjusted EBITDA (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
SEGMENTS
Segment adjusted EBITDA	$ 640	$ 597	$ 1,872	$ 1,556
Workforce rebalancing charges	(19)	(10)	(115)	(16)
Charges related to ceasing to use leased / fixed assets and lease terminations	(14)	(10)	(24)	(10)
Transaction-related (costs) benefits	77	(48)	(12)	(218)
Stock-based compensation expense	(25)	(29)	(72)	(81)
Interest expense	(31)	(27)	(92)	(65)
Depreciation of property, equipment and capitalized software	(207)	(232)	(639)	(681)
Amortization expense	(322)	(336)	(968)	(945)
Corporate expense not allocated to the segments	(25)	(16)	(71)	(57)
Other adjustments	(21)	(27)	(42)	(45)
Income (loss) before income taxes	$ 53	$ (138)	$ (165)	$ (563)