Restructuring, Impairment, and Related Charges - Summary of Restructuring Charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	$ 1	$ 9	$ 14	$ 63
Exit and other-related costs	16	15	66	43
Asset impairments and accelerated depreciation	1	16	128	50
Total	18	40	208	156
International (1)
Restructuring Cost and Reserve [Line Items]
Total		131		189
Operating Segments | U.S. Pharmaceutical
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	0	3	2	10
Exit and other-related costs	3	3	7	8
Asset impairments and accelerated depreciation	0	0	16	0
Total	3	6	25	18
Operating Segments | Prescription Technology Solutions
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	0	0	(1)	0
Exit and other-related costs	0	0	2	0
Asset impairments and accelerated depreciation	0	0	17	0
Total	0	0	18	0
Operating Segments | Medical-Surgical Solutions
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	0	(3)	1	0
Exit and other-related costs	1	1	3	3
Asset impairments and accelerated depreciation	0	0	5	1
Total	1	(2)	9	4
Operating Segments | International (1)
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	0	2	10	22
Exit and other-related costs	6	5	21	12
Asset impairments and accelerated depreciation	(1)	9	35	40
Total	5	16	66	74
Corporate
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	1	7	2	31
Exit and other-related costs	6	6	33	20
Asset impairments and accelerated depreciation	2	7	55	9
Total	$ 9	$ 20	$ 90	$ 60