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Segments of Business - Schedule of Segment Information (Details) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jul. 31, 2022 | Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2023
Segment revenues |  |  |  |
Total revenues |  | $ 359,051 | $ 308,951 | $ 276,711
Other segment expense (income) |  | 353,603 | 304,059 | 271,686
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | 5,437 | 4,892 | 5,025
Interest expense |  | (265) | (252) | (248)
Income from continuing operations before income taxes |  | 4,359 | 3,789 | 4,630
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 636 | 635 | 608
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | 859 | 687 | 558
Provision for bad debts |  | (130) | 819 | 45
Charges (credits) associated with last-in, first-out inventory method |  | 82 | (157) | 1
Restructuring charges |  | 344 | 115 | 209
Income (loss) from equity method investments |  | 9 | 4 | 5
Other income (expense) |  | (38) | 34 | 279
Net gains (losses) on investments in equity securities |  | 101 | (24) | (36)
Gain on derivative termination |  |  |  | 97
Rx Savings Solutions, LLC |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Fair value adjustment gain |  |  | (78) |
Tax Receivable Agreement (“TRA”) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Gain for early termination of tax receivable agreement |  |  |  | 126
Corporate |  |  |  |
Segment revenues |  |  |  |
Total revenues |  | 11 | 0 | 0
Segment operating profit (loss) |  |  |  |
Corporate expenses, net |  | (813) | (851) | (147)
Interest expense |  | (265) | (252) | (248)
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 140 | 121 | 124
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | 337 | 229 | 173
Restructuring charges |  | 68 | 55 | 83
Other income (expense) |  | (87) |  |
Net gains (losses) on investments in equity securities |  | 101 | (24) | (36)
Corporate | National Prescription Opiate Litigation |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Litigation settlement payments |  | 14 | 35 | 36
Corporate | Canadian Retail Disposal Group |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Other comprehensive income (loss) |  | (62) |  |
Corporate | Held-for-sale | E.U. Businesses (Disposal Group) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  |  |  | (306)
Corporate | National Prescription Opiate Litigation |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Loss contingency accrual, period increase (decrease) |  | 51 | 73 | (8)
U.S. Pharmaceutical |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Provision for bad debts |  | (206) | 725 |
U.S. Pharmaceutical | Operating Segments |  |  |  |
Segment revenues |  |  |  |
Total revenues |  | 327,717 | 278,739 | 240,616
Other segment expense (income) |  | 323,715 | 275,953 | 237,410
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | 4,002 | 2,786 | 3,206
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 231 | 229 | 212
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | $ 241 | $ 193 | $ 154
Revenue derived from services, percentage (less than) |  | 1.00% | 1.00% | 1.00%
Net cash proceeds from settlements |  | $ 444 | $ 244 | $ 129
Charges (credits) associated with last-in, first-out inventory method |  | 82 | (157) | 1
Restructuring charges |  | 59 | 17 | 38
Income (loss) from equity method investments |  | (43) |  |
Gain from sale of equity method investment |  |  |  | 142
Proceeds from sale of equity method investment | $ 179 |  |  |
U.S. Pharmaceutical | Operating Segments | National Prescription Opiate Litigation |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Loss contingency accrual, period increase (decrease) |  | 57 | 74 |
Prescription Technology Solutions | Operating Segments |  |  |  |
Segment revenues |  |  |  |
Total revenues |  | 5,216 | 4,769 | 4,387
Other segment expense (income) |  | 4,341 | 3,934 | 3,821
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | 875 | 835 | 566
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 86 | 84 | 77
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | $ 11 | $ 31 | $ 35
Revenue derived from services, percentage (less than) |  | 39.00% | 39.00% | 39.00%
Restructuring charges |  | $ 12 | $ 11 | $ 43
Medical-Surgical Solutions | Operating Segments |  |  |  |
Segment revenues |  |  |  |
Total revenues |  | 11,386 | 11,313 | 11,110
Other segment expense (income) |  | 10,613 | 10,361 | 9,993
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | 773 | 952 | 1,117
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 93 | 84 | 80
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | $ 163 | $ 159 | $ 117
Revenue derived from services, percentage (less than) |  | 1.00% | 1.00% | 1.00%
Restructuring charges |  | $ 204 | $ 11 | $ 10
International | Held-for-sale | Canadian Retail Disposal Group |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  | 605 |  |
International | Operating Segments |  |  |  |
Segment revenues |  |  |  |
Total revenues |  | 14,721 | 14,130 | 20,598
Other segment expense (income) |  | 14,934 | 13,811 | 20,462
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | (213) | 319 | 136
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 86 | 117 | 115
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | $ 107 | $ 75 | $ 79
Revenue derived from services, percentage (less than) |  | 1.00% | 1.00% | 1.00%
Restructuring charges |  | $ 1 | $ 21 | $ 35
International | Operating Segments | Held-for-sale | E.U. Businesses (Disposal Group) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  |  |  | $ 240

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