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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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Percentage of claims participating in litigation settlement.

+ References

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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

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- Definition

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

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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

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