Commitments and Contingent Liabilities - I. Litigation and Claims Involving Distribution of Controlled Substances (Narrative) (Details) $ in Millions		12 Months Ended
	Feb. 25, 2019	Mar. 31, 2024 USD ($) state jurisdiction distributor plaintiff case	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)
Loss Contingencies [Line Items]
Claims and litigation charges, net		$ 147	$ (8)	$ 274
National Prescription Opiate Litigation
Loss Contingencies [Line Items]
Number of jurisdictions that did not participate in settlement | jurisdiction		1
Number of plaintiffs | plaintiff		1
Claims and litigation charges, net		$ 149
Loss contingency, estimate of possible loss		$ 114
Canada | National Prescription Opiate Litigation
Loss Contingencies [Line Items]
Number of complaints served | case		4
UNITED STATES | National Prescription Opiate Litigation
Loss Contingencies [Line Items]
Number of complaints served | case		400
Individual Claimant | Canada | National Prescription Opiate Litigation
Loss Contingencies [Line Items]
Number of complaints served | case		1
Individual Claimant | UNITED STATES | National Prescription Opiate Litigation
Loss Contingencies [Line Items]
Number of complaints served | case		1
National Prescription Opiate Litigation
Loss Contingencies [Line Items]
Number of other defendants | distributor		2
Number of states | state		48
Loss contingency, number of cases dismissed | case		2,300
Litigation settlement, award amount to be used by state and local government		85.00%
National Prescription Opiate Litigation | State of Alabama and Subdivisions
Loss Contingencies [Line Items]
Payments for legal settlements		$ 61
Aggregate amount expected to be paid		113
National Prescription Opiate Litigation | Settling Governmental Entities and Cherokee Nation | Settled Litigation
Loss Contingencies [Line Items]
Payments for legal settlements		$ 544	$ 1,100	$ 74
National Prescription Opiate Litigation | Native American Tribes Other Than Cherokee Nation
Loss Contingencies [Line Items]
Percentage of total settlement to be used to remediate damages (in percent)		0.85
National Prescription Opiate Litigation | Three Largest U.S. Pharmaceutical Distributors
Loss Contingencies [Line Items]
Payments for legal settlements		$ 1,500
Aggregate amount expected to be paid		6,300
National Prescription Opiate Litigation | Three National Pharmaceutical Distributors | State of West Virginia and Subdivisions
Loss Contingencies [Line Items]
Payments for legal settlements		53
National Prescription Opiate Litigation | Three National Pharmaceutical Distributors | State of West Virginia and Subdivisions | Settled Litigation
Loss Contingencies [Line Items]
Aggregate amount expected to be paid		99
National Prescription Opiate Litigation | Three National Pharmaceutical Distributors | Cherokee Nation
Loss Contingencies [Line Items]
Payments for legal settlements		84
Aggregate amount expected to be paid		$ 112
United States ex rel. Manchester v. Purdue Pharma, L.P., et al
Loss Contingencies [Line Items]
Period within which party can be substituted	90 days