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Goodwill and Intangible Assets, Net - Goodwill Narrative (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Jun. 30, 2018 USD ($) reporting_unit | Mar. 31, 2018 USD ($) | Mar. 31, 2020 USD ($) | Mar. 31, 2019 USD ($) reporting_unit | Mar. 31, 2018 USD ($)
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill impairment charge |  |  |  |  | $ 2 | $ 1,797 | $ 1,738
Number of reporting units | reporting_unit |  |  |  |  |  | 2 |
European Pharmaceutical Solutions |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill impairment charge | $ 1,200 |  | $ 570 |  | 0 | $ 1,776 | $ 1,300
Number of reporting units | reporting_unit |  |  | 2 |  |  |  |
Accumulated goodwill impairment loss | 3,100 |  |  |  | 3,100 | 3,100 |
Other |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill impairment charge |  |  |  |  | 2 | 21 |
Accumulated goodwill impairment loss | 476 |  |  |  | $ 478 | 476 |
RP | European Pharmaceutical Solutions |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Tax charged related to impairment |  |  |  |  |  | $ 20 |
Goodwill impairment charge | $ 465 |  | $ 251 |  |  |  |
Rexall Health | Other |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |
Goodwill impairment charge |  | $ 21 |  | $ 455 |  |  |

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- Definition Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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