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Contingencies - Propecia/Proscar Litigation - Narrative (Details) - Propecia/Proscar $ in Millions |  | 3 Months Ended
--- | --- | ---
Apr. 09, 2018 USD ($) | Mar. 31, 2018 Plaintiff legalmatter
Loss Contingencies [Line Items] |  |
Loss contingency, pending claims, number (in legal matters) |  | 600
Subsequent event |  |
Loss Contingencies [Line Items] |  |
Percentage of participation in litigation settlement (as percent) | 95.00% |
Litigation settlement amount to other party | $ | $ 4.3 |
Cases alleging cancer |  |
Loss Contingencies [Line Items] |  |
Number of plaintiffs | Plaintiff |  | 15
Other state courts | California state court |  |
Loss Contingencies [Line Items] |  |
Loss contingency, pending claims, number (in legal matters) |  | 1
Other state courts | Ohio state court |  |
Loss Contingencies [Line Items] |  |
Loss contingency, pending claims, number (in legal matters) |  | 1
Other state courts | Massachusetts state court |  |
Loss Contingencies [Line Items] |  |
Loss contingency, pending claims, number (in legal matters) |  | 1

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- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349 + Details
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