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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, 2023 | Mar. 31, 2022 | Mar. 31, 2021
Segment revenues |  |  |  |
Total revenues |  | $ 276,711 | $ 263,966 | $ 238,228
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | 5,025 | 3,370 | 3,828
Corporate expenses, net |  | (147) | (1,073) | (8,645)
Loss on debt extinguishment |  | 0 | (191) | 0
Interest expense |  | (248) | (178) | (217)
Income (loss) from continuing operations before income taxes |  | 4,630 | 1,928 | (5,034)
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 608 | 760 | 887
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | 558 | 535 | 641
Charges (credits) associated with last-in, first-out inventory method |  | 1 | (23) | (38)
Charge for remeasurement to fair value |  | 0 | 1,509 | 0
Goodwill impairment charge |  | 0 | 0 | 69
Long-lived asset impairment charges, before tax |  | 0 |  |
Gain on derivative termination |  | (97) |  |
Restructuring charges |  | 209 | 245 | 219
Net gains (losses) on investments in equity securities |  | (36) | 98 | 133
Shareholder Derivative Action |  |  |  |
Segment operating profit (loss) |  |  |  |
Corporate expenses, net |  |  |  | (131)
Tax Receivable Agreement (“TRA”) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Gain for early termination of tax receivable agreement |  | 126 |  |
German Wholesale Business |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Gain from sale of equity method investment |  |  | 42 |
Held-for-sale | E.U. Businesses (Disposal Group) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  |  | 438 |
Held-for-sale | U.K. Businesses (Disposal Group) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  |  | 1,200 |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | E.U. Businesses (Disposal Group) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  | (66) |  |
National Prescription Opiate Litigation |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Loss contingency accrual, period increase (decrease) |  | (8) | $ 274 | 8,100
Operating Segments | German Wholesale Business |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Noncontrolling interest (percent) |  |  | 30.00% |
Corporate |  |  |  |
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 124 | $ 117 | 125
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | 173 | 137 | 104
Restructuring charges |  | 83 | 100 | 105
Corporate | National Prescription Opiate Litigation |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Litigation settlement payments |  | 36 | 130 | 153
Corporate | Held-for-sale | E.U. Businesses (Disposal Group) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  | (306) | 55 |
Corporate | Held-for-sale | U.K. Businesses (Disposal Group) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  |  | 42 |
U.S. Pharmaceutical |  |  |  |
Segment revenues |  |  |  |
Total revenues |  | 240,616 | 212,149 | 189,274
U.S. Pharmaceutical | New York Opioid Tax Surcharge |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge recorded related to Company's share of the litigation settlement |  | 18 |  | 50
U.S. Pharmaceutical | Operating Segments |  |  |  |
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | 3,206 | 2,879 | 2,763
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 212 | 228 | 211
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | $ 154 | $ 137 | $ 246
Revenue derived from services, percentage (less than) |  | 1.00% | 1.00% | 1.00%
Net cash proceeds from settlements |  | $ 129 | $ 46 | $ 181
Charges (credits) associated with last-in, first-out inventory method |  | (1) | 23 | 38
Gain from sale of equity method investment |  | 142 |  |
Proceeds from sale of equity method investment | $ 179 |  |  |
Restructuring charges |  | 38 | 35 | 21
U.S. Pharmaceutical | Operating Segments | New York Opioid Tax Surcharge |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge recorded related to Company's share of the litigation settlement |  | 18 |  | 50
Prescription Technology Solutions |  |  |  |
Segment revenues |  |  |  |
Total revenues |  | 4,387 | 3,864 | 2,890
Prescription Technology Solutions | Operating Segments |  |  |  |
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | 566 | 500 | 395
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 77 | 82 | 87
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | $ 35 | $ 10 | $ 22
Revenue derived from services, percentage (less than) |  | 40.00% | 40.00% | 40.00%
Restructuring charges |  | $ 43 | $ 25 | $ 4
Medical-Surgical Solutions |  |  |  |
Segment revenues |  |  |  |
Total revenues |  | 11,110 | 11,608 | 10,099
Segment expenditures for long-lived assets |  |  |  |
Inventory write-down charges |  |  | 164 | 136
Medical-Surgical Solutions | Operating Segments |  |  |  |
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | 1,117 | 959 | 707
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 80 | 129 | 130
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | $ 117 | $ 74 | $ 57
Revenue derived from services, percentage (less than) |  | 2.00% | 2.00% | 2.00%
Restructuring charges |  | $ 10 | $ 9 | $ 4
International |  |  |  |
Segment revenues |  |  |  |
Total revenues |  | 20,598 | 36,345 | 35,965
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  |  |  | 58
Long-lived asset impairment charges, before tax |  |  | 36 |
International | Operating Segments |  |  |  |
Segment operating profit (loss) |  |  |  |
Total operating profit (loss) |  | 136 | (968) | (37)
Segment depreciation and amortization |  |  |  |
Total depreciation and amortization |  | 115 | 204 | 334
Segment expenditures for long-lived assets |  |  |  |
Total expenditures for long-lived assets |  | $ 79 | $ 177 | $ 212
Revenue derived from services, percentage (less than) |  | 8.00% | 8.00% | 8.00%
Goodwill impairment charge |  |  |  | $ 69
Long-lived asset impairment charges, before tax |  |  |  | 115
Restructuring charges |  | $ 35 | $ 76 | $ 85
International | Operating Segments | Held-for-sale | E.U. Businesses (Disposal Group) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  | $ 240 | 383 |
International | Operating Segments | Held-for-sale | U.K. Businesses (Disposal Group) |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Charge for remeasurement to fair value |  |  | 1,100 |
International | Operating Segments | Held-for-sale | German Wholesale Business | Walgreens Boots Alliance Joint Venture |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Gain from sale of equity method investment |  |  | 42 |
International | Operating Segments | Disposal Group, Disposed of by Sale, Not Discontinued Operations | Canadian Health Benefit Claims Management and Plan Administrative Services Business |  |  |  |
Segment expenditures for long-lived assets |  |  |  |
Pre-tax gain on sale of business |  |  | $ 59 |

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