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Contingencies - Propecia/Proscar Litigation - Narrative (Details) - Propecia/Proscar	9 Months Ended
	Sep. 30, 2017 legalmatter Plaintiff
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters)	915
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 Supreme Judicial court
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters)	1
Cases alleging cancer
Loss Contingencies [Line Items]
Number of plaintiffs | Plaintiff	20

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Number of plaintiffs that have filed claims pertaining to a loss contingency.

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Number of pending claims pertaining to a loss contingency.

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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

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