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Commitments and Contingent Liabilities - Litigation and Claims Involving Distribution of Controlled Substances (Narrative) (Details) $ in Millions |  |  | 12 Months Ended
--- | --- | --- | ---
Aug. 08, 2025 USD ($) | Nov. 27, 2024 USD ($) | Mar. 31, 2026 USD ($) case distributor state jurisdiction | Mar. 31, 2025 USD ($) | Mar. 31, 2024 USD ($)
Loss Contingencies [Line Items] |  |  |  |  |
Claims and litigation charges, net |  |  | $ (3.0) | $ 108.0 | $ 147.0
National Prescription Opiate Litigation |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Claims and litigation charges, net |  |  |  | 114.0 |
National Prescription Opiate Litigation | Canada |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Number of complaints served | case |  |  | 4 |  |
Individual Claimant | National Prescription Opiate Litigation | Canada |  |  |  |  |
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% |  |
Aggregate settlement payments expected to be paid |  |  | $ 7,900.0 |  |
Number of jurisdictions that did not participate in settlement | jurisdiction |  |  | 1 |  |
Claims and litigation charges, net |  | $ 149.0 |  |  |
National Prescription Opiate Litigation | Compensatory Damages |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Amounts awarded to plaintiff | $ 37.0 |  |  |  |
National Prescription Opiate Litigation | Monetary Abatement |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Amounts awarded to plaintiff | $ 72.0 |  |  |  |
National Prescription Opiate Litigation | State of Alabama and Subdivisions |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Aggregate settlement payments expected to be paid |  |  | $ 174.0 |  |
National Prescription Opiate Litigation | West Virginia Subdivisions |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Aggregate settlement payments expected to be paid |  |  | 152.0 |  |
National Prescription Opiate Litigation | Native American Tribes Other Than Cherokee Nation |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Payments for legal settlements |  |  | $ 196.0 |  |
Percentage of total settlement to be used to remediate damages (in percent) |  |  | 0.85 |  |
National Prescription Opiate Litigation | Settling Governmental Entities and Cherokee Nation | Settled Litigation |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Payments for legal settlements |  |  | $ 512.0 | $ 515.0 | $ 544.0

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