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Contingencies and Environmental Liabilities - Fosamax Product Liability Litigation - Narrative (Details) - Fosamax - legalmatter	1 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2018	Jul. 31, 2015	Nov. 30, 2013
Loss Contingencies [Line Items]
Loss contingency, pending claims number		3,900
Federal Court
Loss Contingencies [Line Items]
Loss contingency, pending claims number		9
Loss contingency, claims dismissed number	650	1,055
Loss contingency, claims on appeal, number		515
New Jersey State Court
Loss Contingencies [Line Items]
Loss contingency, pending claims number		2,555
Initial number of cases selected for review		30
Subsequent number of cases selected for review	50		25	50
California State Court
Loss Contingencies [Line Items]
Loss contingency, pending claims number		275
Initial number of cases selected for review	10
Other State Court
Loss Contingencies [Line Items]
Loss contingency, pending claims number		4

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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