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Commitments and Contingent Liabilities - Litigation and Claims Involving Distribution of Controlled Substances (Narrative) (Details) $ in Millions |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Jun. 12, 2025 USD ($) | Nov. 12, 2024 USD ($) | Jul. 31, 2025 USD ($) | Jun. 30, 2025 USD ($) case distributor jurisdiction state | Jun. 30, 2024 USD ($) | Mar. 31, 2025 USD ($) | Mar. 31, 2024 USD ($) | Nov. 27, 2024 USD ($)
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Claims and litigation charges |  |  |  | $ 0 | $ (112) |  |  |
National Prescription Opioid Litigation |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Loss contingency, claims settled, number of jurisdictions not participating in settlement | jurisdiction |  |  |  | 1 |  |  |  |
National Prescription Opioid Litigation | Canada |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Complaints filed against the entity | case |  |  |  | 4 |  |  |  |
An individual | National Prescription Opioid Litigation | Canada |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Complaints filed against the entity | case |  |  |  | 1 |  |  |  |
National Prescription Opioid Litigation |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Number of other national distributors named in suit | distributor |  |  |  | 2 |  |  |  |
Number of states in which court cases are pending | state |  |  |  | 48 |  |  |  |
Loss contingency, number of cases dismissed | case |  |  |  | 2,300 |  |  |  |
Portion of settlement award to be used by state and local government for remediation (as a percent) |  |  |  | 85.00% |  |  |  |
Amounts awarded to plaintiff | $ 37 | $ 192 |  |  |  |  |  |
Claims and litigation charges |  |  |  |  |  | $ 114 | $ 149 |
Restricted cash in escrow |  |  |  |  |  | 114 |  | $ 149
National Prescription Opioid Litigation | Corporate Segment and U.S. Pharmaceutical Segment |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Claims and litigation charges |  |  |  |  |  | $ 57 |  |
National Prescription Opioid Litigation | State of Alabama and Subdivisions |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Settlement payment |  |  |  | $ 75 |  |  |  |
Award payable under proposed framework |  |  |  | $ 99 |  |  |  |
National Prescription Opioid Litigation | Native American Tribes Other Than Cherokee Nation |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Litigation settlement, amount awarded to other party, percentage of total settlement to be used to remediate damages (as a percent) |  |  |  | 0.85 |  |  |  |
National Prescription Opioid Litigation | Settling Governmental Entities and Cherokee Nation | Settled Litigation | Subsequent Event |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Settlement payment |  |  | $ 497 |  |  |  |  |
National Prescription Opioid Litigation | Three Largest U.S. Pharmaceutical Distributors |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Settlement payment |  |  |  | $ 2,000 |  |  |  |
Award payable under proposed framework |  |  |  | 5,900 |  |  |  |
National Prescription Opioid Litigation | Three National Pharmaceutical Distributors | State of West Virginia and Subdivisions |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Settlement payment |  |  |  | 68 |  |  |  |
National Prescription Opioid Litigation | Three National Pharmaceutical Distributors | State of West Virginia and Subdivisions | Settled Litigation |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Award payable under proposed framework |  |  |  | 84 |  |  |  |
National Prescription Opioid Litigation | Three National Pharmaceutical Distributors | Cherokee Nation |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Settlement payment |  |  |  | 112 |  |  |  |
Award payable under proposed framework |  |  |  | $ 84 |  |  |  |

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