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Segments of Business (Details) numberOfProducts in Thousands, $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended
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Dec. 31, 2020 USD ($) business_operation country numberOfProducts | Sep. 30, 2020 USD ($) segment | Dec. 31, 2019 USD ($) | Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Dec. 31, 2020 segment business_operation country numberOfProducts | Dec. 31, 2020 USD ($) business_operation country numberOfProducts | Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Number of reportable segments | segment |  | 4 |  |  |  | 4 |  |
Segment revenues |  |  |  |  |  |  |  |
Total revenues | $ 62,599.0 |  | $ 59,172.0 |  |  |  | $ 179,086.0 | $ 172,516.0
Segment operating profit (loss) |  |  |  |  |  |  |  |
Total operating profit (loss) | (7,362.0) |  | 360.0 |  |  |  | (6,050.0) | 1,620.0
Corporate income (expenses), net | (8,246.0) |  | (202.0) |  |  |  | (8,462.0) | (713.0)
Interest expense | (55.0) |  | (64.0) |  |  |  | (165.0) | (184.0)
Income (loss) from continuing operations before income taxes | (7,363.0) |  | 294.0 |  |  |  | (6,063.0) | (57.0)
Pre-tax credits related to LIFO accounting |  |  |  |  |  |  | 115.0 | 114.0
Restructuring, impairment, and related charges | 40.0 |  | 42.0 |  |  |  | 156.0 | 110.0
Goodwill and other asset impairment charges |  |  |  |  |  |  | 236.0 | 113.0
Goodwill impairment charge | 0.0 |  | 2.0 |  |  |  | 69.0 | 2.0
Net gains associated with equity investments | 30.0 |  |  |  |  |  | 89.0 |
German Wholesale Business |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Pre-tax loss on sale of business | 47.0 |  |  |  |  |  | 57.0 |
After-tax loss on sale of business | 47.0 |  |  |  |  |  |  |
National Prescription Opioid Litigation |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Pre-tax expenses related to estimated litigation liability | 8,100.0 |  |  |  |  |  | 8,100.0 |
After-tax expenses related to estimated litigation liability | 6,700.0 |  |  |  |  |  | 6,700.0 |
Joint Venture | Change Healthcare JV |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Impairment |  |  |  | $ 1,200.0 |  |  |  | 1,200.0
Pre-tax dilution loss |  |  |  | $ 246.0 |  |  |  | 246.0
Proportionate loss from investment in Change Healthcare |  |  | 28.0 |  |  |  |  | 75.0
United States | Pension Plan |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Pre-tax settlement expense |  |  |  |  | $ 17.0 |  |  | 122.0
National Prescription Opioid Litigation |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Corporate income (expenses), net |  |  |  |  |  |  | 131.0 |
Charge in connection with State of New York's Opioid Stewardship Act |  |  |  |  |  |  | 50.0 |
Opioid-related settlement charges |  |  |  |  |  |  |  | 82.0
Pre-tax litigation expense | 34.0 |  | 36.0 |  |  |  | 118.0 | 108.0
United States |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Number of reportable segments | segment |  |  |  |  |  | 3 |  |
U.K and Canada |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Restructuring, impairment, and related charges |  |  | 100.0 |  |  |  |  | 116.0
Operating Segments |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Total operating profit (loss) | 938.0 |  | 560.0 |  |  |  | 2,564.0 | 840.0
Corporate |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Total operating profit (loss) | 0.0 |  | (33.0) |  |  |  | 0.0 | (1,483.0)
Restructuring, impairment, and related charges | 20.0 |  | 23.0 |  |  |  | 60.0 | 67.0
U.S. Pharmaceutical |  |  |  |  |  |  |  |
Segment revenues |  |  |  |  |  |  |  |
Total revenues | 49,495.0 |  | 46,453.0 |  |  |  | 142,232.0 | 135,855.0
Segment operating profit (loss) |  |  |  |  |  |  |  |
Pre-tax credits related to LIFO accounting | 11.0 |  | 66.0 |  |  |  | 115.0 | 114.0
Goodwill impairment charge |  |  |  |  |  |  | 0.0 |
U.S. Pharmaceutical | Operating Segments |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Total operating profit (loss) | 635.0 |  | 677.0 |  |  |  | $ 1,871.0 | $ 1,894.0
Revenue derived from services, percentage (less than) |  |  |  |  |  |  | 1.00% | 1.00%
Restructuring, impairment, and related charges | 6.0 |  | 7.0 |  |  |  | $ 18.0 | $ 9.0
International |  |  |  |  |  |  |  |
Segment revenues |  |  |  |  |  |  |  |
Total revenues | 9,273.0 |  | 9,864.0 |  |  |  | 27,365.0 | 28,592.0
Segment operating profit (loss) |  |  |  |  |  |  |  |
Restructuring, impairment, and related charges | 131.0 |  |  |  |  |  | 189.0 |
Goodwill and other asset impairment charges | 115.0 |  | 94.0 |  |  |  | 115.0 | 94.0
Goodwill impairment charge |  | $ 69.0 |  |  |  |  | 69.0 |
After-tax goodwill impairment |  | $ 69.0 |  |  |  |  | 69.0 |
International | Strategic Growth Initiative Plan |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Restructuring, impairment, and related charges | $ 9.0 |  |  |  |  |  | $ 50.0 |
International | Europe |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Number of countries in which entity segment operates | country | 13 |  |  |  |  | 13 | 13 |
Number of business operations | business_operation | 2 |  |  |  |  | 2 | 2 |
International | Operating Segments |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Total operating profit (loss) | $ (71.0) |  | (290.0) |  |  |  | $ (113.0) | $ (229.0)
Revenue derived from services, percentage (less than) |  |  |  |  |  |  | 7.00% | 7.00%
Restructuring, impairment, and related charges | $ 16.0 |  | 6.0 |  |  |  | $ 74.0 | $ 22.0
Medical-Surgical Solutions |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |
Number of national brand medical-surgical products offered (more than) | numberOfProducts | 275 |  |  |  |  | 275 | 275 |
Segment revenues |  |  |  |  |  |  |  |
Total revenues | $ 3,054.0 |  | 2,141.0 |  |  |  | $ 7,388.0 | 6,100.0
Segment operating profit (loss) |  |  |  |  |  |  |  |
Goodwill impairment charge |  |  |  |  |  |  | 0.0 |
Inventory impairments and excess inventory | 35.0 |  |  |  |  |  | 49.0 |
Medical-Surgical Solutions | Operating Segments |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Total operating profit (loss) | 260.0 |  | 124.0 |  |  |  | $ 536.0 | $ 378.0
Revenue derived from services, percentage (less than) |  |  |  |  |  |  | 2.00% | 2.00%
Restructuring, impairment, and related charges | (2.0) |  | 6.0 |  |  |  | $ 4.0 | $ 12.0
Prescription Technology Solutions |  |  |  |  |  |  |  |
Segment revenues |  |  |  |  |  |  |  |
Total revenues | 777.0 |  | 714.0 |  |  |  | 2,101.0 | 1,969.0
Prescription Technology Solutions | Operating Segments |  |  |  |  |  |  |  |
Segment operating profit (loss) |  |  |  |  |  |  |  |
Total operating profit (loss) | 114.0 |  | 82.0 |  |  |  | $ 270.0 | $ 280.0
Revenue derived from services, percentage (less than) |  |  |  |  |  |  | 38.00% | 38.00%
Restructuring, impairment, and related charges | $ 0.0 |  | $ 0.0 |  |  |  | $ 0.0 | $ 0.0

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