Restructuring, Impairment, and Related Charges, Net - Summary of Restructuring Activity (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Restructuring Reserve [Roll Forward]
Beginning balance			$ 92
Restructuring, impairment, and related charges, net	$ 28	$ 30	80	$ 53
Non-cash charges			(28)
Cash payments			(68)
Other			(10)
Ending balance	66		66
Operating Segments | U.S. Pharmaceutical
Restructuring Reserve [Roll Forward]
Beginning balance			15
Restructuring, impairment, and related charges, net	9	3	11	7
Non-cash charges			0
Cash payments			(10)
Other			0
Ending balance	16		16
Operating Segments | Prescription Technology Solutions
Restructuring Reserve [Roll Forward]
Beginning balance			26
Restructuring, impairment, and related charges, net	3	7	5	14
Non-cash charges			0
Cash payments			(26)
Other			0
Ending balance	5		5
Operating Segments | Medical-Surgical Solutions
Restructuring Reserve [Roll Forward]
Beginning balance			3
Restructuring, impairment, and related charges, net	4	1	6	2
Non-cash charges			0
Cash payments			(6)
Other			0
Ending balance	3		3
Operating Segments | International
Restructuring Reserve [Roll Forward]
Beginning balance			13
Restructuring, impairment, and related charges, net	6	9	12	11
Non-cash charges			(1)
Cash payments			(3)
Other			(10)
Ending balance	11		11
Corporate
Restructuring Reserve [Roll Forward]
Beginning balance			35
Restructuring, impairment, and related charges, net	6	$ 10	46	$ 19
Non-cash charges			(27)
Cash payments			(23)
Other			0
Ending balance	31		31
Accrued Liabilities
Restructuring Reserve [Roll Forward]
Beginning balance			66
Ending balance	32		32
Other Non-Current Liabilities
Restructuring Reserve [Roll Forward]
Beginning balance			26
Ending balance	$ 34		$ 34