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Segments of Business (Details) $ in Millions, $ in Millions |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
May 23, 2018 USD ($) | May 23, 2018 CAD ($) | Sep. 30, 2019 USD ($) country | Jun. 30, 2019 USD ($) | Sep. 30, 2018 USD ($) | Sep. 30, 2019 USD ($) segment country | Sep. 30, 2018 USD ($)
Segment Reporting Information [Line Items] |  |  |  |  |  |  |
Number of reportable segments | segment |  |  |  |  |  | 3 |
Revenues |  |  |  |  |  |  |
Total Revenues |  |  | $ 57,616 |  | $ 53,075 | $ 113,344 | $ 105,682
Operating profit |  |  |  |  |  |  |
Total operating profit |  |  | 626 |  | 689 | 1,260 | 772
Corporate Expenses, Net |  |  | (364) |  | (167) | (539) | (290)
Interest Expense |  |  | (64) |  | (66) | (120) | (127)
Income (Loss) from Continuing Operations Before Income Taxes |  |  | (970) |  | 587 | (351) | 593
Pre-tax credits related to LIFO accounting |  |  |  |  |  | 48 | 43
Proceeds from legal settlements |  |  |  |  |  |  | 35
Pretax goodwill impairment charges |  |  | 0 |  | 0 | 0 | 570
Net restructuring charges recognized |  |  | 45 |  | 82 | 68 | 178
Net restructuring charges recognized, after tax |  |  | 35 |  | 67 | 52 | 152
Loss from investment in Change Healthcare Joint Venture |  |  | 1,454 |  | 56 | 1,450 | 112
U.S. Pharmaceutical and Specialty Solutions |  |  |  |  |  |  |
Operating profit |  |  |  |  |  |  |
Pre-tax credits related to LIFO accounting |  |  | $ 33 |  | 22 | $ 48 | 43
European Pharmaceutical Solutions |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |
Number of countries in which entity segment operates | country |  |  | 13 |  |  | 13 |
Operating profit |  |  |  |  |  |  |
Pretax goodwill impairment charges |  |  |  |  |  |  | 570
After-tax goodwill impairment |  |  |  |  |  |  | 570
Operating Segments |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |
Total Revenues |  |  | $ 57,616 |  | 53,075 | $ 113,344 | 105,682
Operating profit |  |  |  |  |  |  |
Total operating profit |  |  | (542) |  | 820 | 308 | 1,010
Operating Segments | U.S. Pharmaceutical and Specialty Solutions |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |
Total Revenues |  |  | 45,979 |  | 41,610 | 90,144 | 82,587
Operating profit |  |  |  |  |  |  |
Total operating profit |  |  | $ 639 |  | $ 610 | $ 1,218 | $ 1,153
Revenue derived from services, percentage (less than) |  |  | 1.00% |  | 1.00% | 1.00% | 1.00%
Operating Segments | European Pharmaceutical Solutions |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |
Total Revenues |  |  | $ 6,598 |  | $ 6,639 | $ 13,308 | $ 13,574
Operating profit |  |  |  |  |  |  |
Total operating profit |  |  | $ 1 |  | $ 10 | $ 6 | $ (550)
Revenue derived from services, percentage (less than) |  |  | 10.00% |  | 10.00% | 10.00% | 10.00%
Operating Segments | Medical-Surgical Solutions |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |
Total Revenues |  |  | $ 2,056 |  | $ 1,948 | $ 3,959 | $ 3,651
Operating profit |  |  |  |  |  |  |
Total operating profit |  |  | $ 129 |  | $ 105 | $ 254 | $ 198
Revenue derived from services, percentage (less than) |  |  | 2.00% |  | 2.00% | 2.00% | 2.00%
Operating Segments | Other |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |
Total Revenues |  |  | $ 2,983 |  | $ 2,878 | $ 5,933 | $ 5,870
Operating profit |  |  |  |  |  |  |
Total operating profit |  |  | (1,311) |  | 95 | (1,170) | 209
Joint Venture |  |  |  |  |  |  |
Operating profit |  |  |  |  |  |  |
Pre-tax credit recognized on relief from potential future obligations |  |  |  |  | 90 |  | 90
Pre-tax dilution loss from reduction of ownership |  |  | (246) |  |  |  |
After-tax dilution loss from reduction of ownership |  |  | (184) |  |  |  |
Gain on escrow settlement |  |  |  |  |  |  | 66
Joint Venture | Change Healthcare JV |  |  |  |  |  |  |
Operating profit |  |  |  |  |  |  |
Pre-tax impairment charge |  |  | 1,157 |  |  |  |
Loss from investment in Change Healthcare Joint Venture |  |  | 51 |  | 56 | 47 | 112
United States |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |
Total Revenues |  |  | 48,292 |  | 43,774 | 94,614 | 86,664
Foreign |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |
Total Revenues |  |  | 9,324 |  | 9,301 | 18,730 | 19,018
Canada | Other |  |  |  |  |  |  |
Operating profit |  |  |  |  |  |  |
Net restructuring charges recognized |  |  |  |  | 42 |  | 80
Third Party Seller of Rexall Health | Rexall Health | Canada |  |  |  |  |  |  |
Operating profit |  |  |  |  |  |  |
Escrow settlement gain, pre-tax | $ 97 | $ 125 |  |  |  |  | 97
Escrow settlement gain, net of tax |  |  |  |  |  |  | 97
United States | Pension Plan |  |  |  |  |  |  |
Operating profit |  |  |  |  |  |  |
Pre-tax settlement expense |  |  | 105 |  |  | 122 |
After-tax settlement expense |  |  | 78 | $ 12 |  |  |
Pre-tax litigation and other-related expenses |  |  | 36 |  | $ 43 | 72 | $ 59
In re: National Prescription Opioid Litigation |  |  |  |  |  |  |
Operating profit |  |  |  |  |  |  |
Pre-tax litigation and other-related expenses |  |  |  |  |  | (82) |
After-tax litigation and other-related expenses |  |  | $ (82) |  |  | $ (82) |

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