Restructuring, Impairment, and Related Charges - Summary of Restructuring Activity (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Restructuring Reserve [Roll Forward]
Beginning balance			$ 151
Restructuring, impairment, and related charges	$ 18	$ 40	208	$ 156
Non-cash charges			(128)
Cash payments			(69)
Other			(18)
Ending balance	144		144
International (1)
Restructuring Reserve [Roll Forward]
Restructuring, impairment, and related charges		131		189
Operating Segments | U.S. Pharmaceutical
Restructuring Reserve [Roll Forward]
Beginning balance			19
Restructuring, impairment, and related charges	3	6	25	18
Non-cash charges			(16)
Cash payments			(15)
Other			0
Ending balance	13		13
Operating Segments | Prescription Technology Solutions
Restructuring Reserve [Roll Forward]
Beginning balance			4
Restructuring, impairment, and related charges	0	0	18	0
Non-cash charges			(17)
Cash payments			(1)
Other			0
Ending balance	4		4
Operating Segments | Medical-Surgical Solutions
Restructuring Reserve [Roll Forward]
Beginning balance			3
Restructuring, impairment, and related charges	1	(2)	9	4
Non-cash charges			(5)
Cash payments			(5)
Other			0
Ending balance	2		2
Operating Segments | International (1)
Restructuring Reserve [Roll Forward]
Beginning balance			66
Restructuring, impairment, and related charges	5	16	66	74
Non-cash charges			(35)
Cash payments			(22)
Other			(11)
Ending balance	64		64
Corporate
Restructuring Reserve [Roll Forward]
Beginning balance			59
Restructuring, impairment, and related charges	9	$ 20	90	$ 60
Non-cash charges			(55)
Cash payments			(26)
Other			(7)
Ending balance	61		61
Other accrued liabilities
Restructuring Reserve [Roll Forward]
Beginning balance			99
Ending balance	52		52
Liabilities held for sale
Restructuring Reserve [Roll Forward]
Ending balance	44		44
Other accrued liabilities, noncurrent
Restructuring Reserve [Roll Forward]
Beginning balance			52
Ending balance	$ 48		$ 48