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Restructuring, Impairment, and Related Charges, Net - Schedule of Restructuring Activity (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023
Restructuring Reserve [Roll Forward]
Beginning balance			$ 55
Restructuring, impairment, and related charges, net	$ 32	$ 4	276	$ 84
Non-cash charges			(83)
Cash payments			(79)
Other			(12)
Ending balance	157		157
Restructuring liabilities	157		157
Operating Segments \| U.S. Pharmaceutical
Restructuring Reserve [Roll Forward]
Beginning balance			18
Restructuring, impairment, and related charges, net	2	(5)	67	6
Non-cash charges			(65)
Cash payments			(4)
Other			(1)
Ending balance	15		15
Restructuring liabilities	15		15
Operating Segments \| Prescription Technology Solutions
Restructuring Reserve [Roll Forward]
Beginning balance			5
Restructuring, impairment, and related charges, net	0	2	5	7
Non-cash charges			(2)
Cash payments			(4)
Other			(2)
Ending balance	2		2
Restructuring liabilities	2		2
Operating Segments \| Medical-Surgical Solutions
Restructuring Reserve [Roll Forward]
Beginning balance			1
Restructuring, impairment, and related charges, net	19	3	169	9
Non-cash charges			(6)
Cash payments			(51)
Other			(2)
Ending balance	111		111
Restructuring liabilities	111		111
Operating Segments \| International
Restructuring Reserve [Roll Forward]
Beginning balance			10
Restructuring, impairment, and related charges, net	1	0	1	12
Non-cash charges			(1)
Cash payments			(2)
Other			(6)
Ending balance	2		2
Restructuring liabilities	2		2
Corporate
Restructuring Reserve [Roll Forward]
Beginning balance			21
Restructuring, impairment, and related charges, net	10	$ 4	34	$ 50
Non-cash charges			(9)
Cash payments			(18)
Other			(1)
Ending balance	27		27
Restructuring liabilities	27		27
Accrued Liabilities
Restructuring Reserve [Roll Forward]
Beginning balance			24
Ending balance	129		129
Restructuring liabilities	129		129
Other Non-Current Liabilities
Restructuring Reserve [Roll Forward]
Beginning balance			31
Ending balance	28		28
Restructuring liabilities	$ 28		$ 28