Restructuring, Impairment, and Related Charges, Net - Schedule of Activity Related to the Liabilities (Details) $ in Millions	3 Months Ended
Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)
Restructuring Reserve [Roll Forward]
Beginning balance	$ 44
Restructuring, impairment, and related charges, net	136	$ 47
Non-cash charges	(47)
Cash payments	(59)
Ending balance	74
Total reserve balance	74
Operating Segments \| North American Pharmaceutical
Restructuring Reserve [Roll Forward]
Beginning balance	18
Restructuring, impairment, and related charges, net	2	1
Non-cash charges	(1)
Cash payments	(3)
Ending balance	16
Total reserve balance	16
Operating Segments \| Prescription Technology Solutions
Restructuring Reserve [Roll Forward]
Beginning balance	3
Restructuring, impairment, and related charges, net	61
Non-cash charges	(40)
Cash payments	0
Ending balance	24
Total reserve balance	24
Operating Segments \| Medical-Surgical Solutions
Restructuring Reserve [Roll Forward]
Beginning balance	10
Restructuring, impairment, and related charges, net	23	17
Non-cash charges	0
Cash payments	(16)
Ending balance	17
Total reserve balance	17
Corporate
Restructuring Reserve [Roll Forward]
Beginning balance	13
Restructuring, impairment, and related charges, net	50	$ 29
Non-cash charges	(6)
Cash payments	(40)
Ending balance	17
Total reserve balance	17
Balance Sheet Location [Axis]: us-gaap:AccruedLiabilitiesCurrent
Restructuring Reserve [Roll Forward]
Beginning balance	30
Ending balance	51
Total reserve balance	51
Balance Sheet Location [Axis]: us-gaap:OtherLiabilitiesNoncurrent
Restructuring Reserve [Roll Forward]
Beginning balance	14
Ending balance	23
Total reserve balance	$ 23

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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