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Contingencies - Narrative (Details) $ in Millions	1 Months Ended	6 Months Ended
	Mar. 31, 2014 Case	Jun. 30, 2019 USD ($) Claim Case	Dec. 31, 2018 USD ($)
Legal Defense Costs
Loss Contingencies [Line Items]
Legal defense costs reserve | $		$ 260	$ 245
Fosamax
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters)		3,900
Fosamax | Femur Fracture Litigation | Federal
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters)		11
Loss contingency, claims dismissed, number (in legal matters)	650	1,060
Loss contingency, claims on appeal, number (in legal matters)	515
Fosamax | Femur Fracture Litigation | New Jersey state court
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters)		2,555
Fosamax | Femur Fracture Litigation | California state court
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters)		275
Fosamax | Femur Fracture Litigation | Other state courts
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters)		4
Januvia
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters) | Claim		1,350
Januvia | Other state courts
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters) | Claim		7
Januvia | Cases Company Agreed To Toll Statute Of Limitations
Loss Contingencies [Line Items]
Loss contingency, pending claims, number (in legal matters) | Claim		50

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- Definition

Loss Contingency, Claims on Appeal, Number

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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
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